batterydata/paper-abstracts huggingface dataset:
Laryngoscopes are an essential and necessary piece of equipment used by anesthesiologist on a daily basis. Early designs of laryngoscopes date back as early as the 1700’s, however, significant innovation and modifications began to take place in 1913 and have continued to the present day [1]. Critical to the operation of laryngoscopes is the requirement of a functional light source. While recent designs of laryngoscopes incorporate high efficiency Light Emitting Diodes (LED) as light sources, they still require power from a stored source that is either rechargeable or disposable. This can become a challenge in low resource settings where batteries or electricity are not readily accessible. An investigation of health facilities in 11 sub-Saharan African countries revealed that 26% of health facilities and 1% of hospitals had no access to electricity. Similarly, 6% of hospitals relied on generator-only power, and 66% of hospitals were classified as not having reliable access to electricity [2]. Furthermore, batteries are expensive, often difficult to acquire and their performance deteriorates over time. Batteries that are not properly recycled lead to toxic effects on the environment and potentially harmful consequences to the surrounding communities. In an effort to create a novel laryngoscope with a completely renewable energy source, we sought to design and evaluate a novel human-thermal powered laryngoscope based on the Seebeck effect.
The present study describes the synthesis of nanocomposite materials based on chromium oxide (Cr2O3) nanoparticles and carbon nanotubes (CNTs) (Cr2O3–CNT(x%)) by in-situ chemical co-precipitation method. The physical studies of these materials using a wide range of analytical techniques reveal high surface area and narrow pore size distribution of these nanocomposite materials, indicating homogenous dispersion of Cr2O3 nanoparticles (particle sizes ∼20-30nm) on the surface of CNTs. The first cycle discharge capacity of 1120 mAhg -1 for electrodes fabricated from Cr2O3 alone, which is improved for Cr2O3–CNT(0.08%) nanocomposite (1199 mAhg -1 ). This nanocomposite material achieved an overall reversible capacity of 995.3 mAhg -1 after 200 cycles, which can be attributed to the high surface area and the large mesoporous volume of Cr2O3 nanoparticles interconnected with highly conducting network of CNTs. At higher current densities, the Cr2O3–CNT(x%) nanocomposite electrodes exhibited high lithium storage capacity compared to the electrode fabricated from Cr2O3 nanoparticles alone. Overall, the Cr2O3–CNT(0.08%) nanocomposite electrode displayed high stability under varying current rates with overall high capacity retention and highest reversible capacity of 719 mAhg -1 at a current rate of 2000 mAhg -1 . This highly enhanced rate capability and excellent cycling stability of Cr2O3–CNT(0.08%) nanocomposite electrode can be ascribed to the synergistic effect of CNTs (anchored with the Cr2O3 nanoparticles). The outcome of this study offers a possibility of improving lithium ion storage of Cr2O3 nanoparticles by carefully controlling their size and shape along with the use of a suitable buffering matrix like CNTs.
We report on the preparation of Li+ conducting lithium phosphorus oxynitride (LiPON) layers by ion beam sputtering, resulting in ultra-thin layers with a thickness down to only 12 nm. The morphology of the layers is studied by transmission electron microscopy, whereas homogeneity and excellent interface quality is observed. The ion conducting properties of the layers are studied as a function of temperature and layer thickness, using electrochemical impedance spectroscopy. In these measurements, a specific ionic conductivity at room temperature of around 2 · 10−7 S cm−1 is found that results in a maximum conductance of 0.2 S cm−2, thanks to their ultra-small thickness. To demonstrate the applicability of the thin films as functional solid state electrolyte, Ag/LiPON/Pt triple layers are studied, serving as models for all solid state batteries. The functionality of these model batteries is measured by cyclic voltammetry of up to 100 charge–discharge cycles, and their morphology after cycling is investigated by transmission electron microscopy. For the first time, these investigations give insight into the morphology of this kind of model cell after intensive cycling. In particular, they allow determining the specific lithium storage capacity of the interface reaction layer between Ag and LiPON, which is found to be around 12 μAh cm−2 μm−1.
A novel neutron diffraction cell has been constructed to allow in-situ studies of the structural changes in materials of relevance to battery applications during charge/discharge cycling. The new design is based on the coin cell geometry, but has larger dimensions compared to typical commercial batteries in order to maximize the amount of electrode material and thus, collect diffraction data of good statistical quality within the shortest possible time. An important aspect of the design is its modular nature, allowing flexibility in both the materials studied and the battery configuration. This paper reports electrochemical tests using a Nickel-metal-hydride battery (Ni-MH), which show that the cell is able to deliver 90% of its theoretical capacity when using deuterated components. Neutron diffraction studies performed on the Polaris diffractometer using nickel metal and a hydrogen-absorbing alloy (MH) clearly show observable changes in the neutron diffraction patterns as a function of the discharge state. Due to the high quality of the diffraction patterns collected in-situ (i.e. good peak-to-background ratio), phase analysis and peak indexing can be performed successfully using data collected in around 30 min. In addition to this, structural parameters for the β-phase (charged) MH electrode obtained by Rietveld refinement are presented.
Concentrated photovoltaic thermal (CPVT) solar collectors have been gaining ever-increasing attention from the scientific community and industrial developers due to their promising potential to pave the way for the penetration of solar energy into modern day power generation technologies. CPVTs׳ flexibility, manufacturability, high efficiency, and multi-output nature inspired many innovative designs and design improvements available in the literature. In this study, a comprehensive, up-to-date review of the governing scientific basics, system variations, and technological advances in CPVT systems will be presented. The study is split into two parts. The first part covers CPVTs’ characteristics and design considerations in addition to an overview of the principals and technological advances in the solar components that compose a CPVT (i.e., solar photovoltaics, solar thermal collectors, solar concentrator optics, and concentrated solar technologies). While the second part thoroughly covers CPVTs׳ published studies, application areas, performance assessment, commercial initiatives, and research prospects.
Mechanical amplification of acoustic signals is apparently a common feature of vertebrate auditory organs. In non-mammalian vertebrates amplification is produced by stereociliary processes, related to the mechanotransducer channel complex and probably to the phenomenon of fast adaptation. The extended frequency range of the mammalian cochlea has probably co-evolved with a novel hair cell type, the outer hair cell and its constituent membrane protein, prestin. Cylindrical outer hair cells are motile and their somatic length changes are voltage driven and powered by prestin. One of the central outstanding problems in mammalian cochlear neurobiology is the relation between the two amplification processes.
In large battery assemblies, which are integrated, for example, in electric vehicles or stationary storage systems, up to several thousand single battery cells are connected together. Every single cell connection influences the functionality and efficiency of the whole battery system. Resistance spot, ultrasonic or laser beam welding are mostly used for connecting battery cells in the production of large battery assemblies. Each of these welding techniques has its own characteristics depending on the material properties and contact geometry. Cell casing and terminal dimensions may constrain possible contact geometries. For example, pouch cells provide detached tabs, whereas cells with hard casing provide a certain area of the casing for electrical connection. Consequently, it is a challenging task to find the most suitable welding technique and welding parameters for each individual battery assembly. This paper presents a comprehensive overview on joining battery cells by resistance spot, ultrasonic and laser beam welding. The specific features, advantages and dependencies of each welding technique for connecting cells are discussed. In addition, a quantitative analysis on welded test samples reveals the ultimate tensile strength and heat input into a battery cell. A novel measuring and calculation method was designed and applied to assess the electrical contact resistance itself. The electrical contact resistance occurs as a result of the joint and not in the bulk material. Therefore, it is a criterion which may be transferred to any size of joint partners.
Modern Cloud Data Centers exploit virtualization for efficient resource management to reduce cloud computational cost and energy budget. Virtualization empowered by virtual machine (VM) migration meets the ever increasing demands of dynamic workload by relocating VMs within Cloud Data Centers. VM migration helps successfully achieve various resource management objectives such as load balancing, power management, fault tolerance, and system maintenance. However, being resource-intensive, the VM migration process rigorously affects application performance unless attended by smart optimization methods. Furthermore, a Cloud Data Centre exploits server consolidation and DVFS methods to optimize energy consumption. This paper reviews state-of-the-art bandwidth optimization schemes, server consolidation frameworks, DVFS-enabled power optimization, and storage optimization methods over WAN links. Through a meticulous literature review of state-of-the-art live VM migration schemes, thematic taxonomies are proposed to categorize the reported literature. The critical aspects of virtual machine migration schemes are investigated through a comprehensive analysis of the existing schemes. The commonalties and differences among existing VM migration schemes are highlighted through a set of parameters derived from the literature. Finally, open research issues and trends in the VM migration domain that necessitate further consideration to develop optimal VM migration schemes are highlighted.
The zirconium fumarate metal-organic framework (MOF-801) and mesoporous carbon (MC) composite was prepared by a conventional method. Compared with MOF-801, MOF-801/MC has a larger specific surface area, pore volume, improved conductivity, and better electrocatalytic performance. The new electrochemical sensor based on MOF-801/MC exhibits significant electrocatalytic activity for the oxidation of GA and the redox of luteolin. And the mechanisms of these two substances are discussed. Under the optimum test conditions, the detection of GA displays a wider linear range, consisted of two linear segments (0.2–5 and 5–100 μM) and the limit of detection (LOD) is 0.15 μM (S/N = 3). At the same time, the detection of luteolin also exhibits two linear relationships, 0.02–0.2 and 0.2–10 μM with LOD of 2.90 nM (S/N = 3). In addition, the MOF-801/MC sensor has good stability, selectivity and reproducibility. MOF-801/MC/GCE sensor was also used for detection of GA and luteolin in green tea and urine with satisfactory results.
The green conversion of germanium dioxide into soluble non-halogenated forms suitable for further processing occurs smoothly and in high yields under the action of 3,5-di-tert-butylbenzene-1,2-diol in presence of biologically active N-donor ligands L. The formed hexacoordinated germanium catecholate complexes (DTBCat)2GeL2 (DTBCat = 3,5-di-tert-butylcatecholate, L = nicotinic acid, nicotinamide and isoniazid) 1–3 are air stable and soluble in common organic solvents. These new complexes are easily reducible at a glassy carbon electrode in DMF/0.1 M Bu4NBF4 at the cathodic potentials remarkably less negative than those of the reduction of parent non-coordinated N-donor ligands L; the corresponding anodic shifts for 1–3 are 0.598, 1.009 and 0.978 V, respectively. The ease of the electrochemical reduction and the energy of electron donation from the ligands L to germanium in 1–3 are in good agreement with DFT B3LYP/def2tzvp analysis and the stabilization energies of these germanium complexes.
Background Profile and correlates of cognitive deficits in first episode (FE) schizophrenia patients are still debated. The present study is aimed to clarify in a large sample of FE patients the extent of impairment in key cognitive domains and its relationships with demographic and clinical variables. Method The European First Episode Schizophrenia Trial collected demographic, clinical and neurocognitive baseline data in 498 FE patients with minimal or no prior exposure to antipsychotics. Two-hundred-twenty healthy subjects (HS) were also evaluated. Neurocognitive assessment included the Rey Auditory Verbal Learning Test; Trail Making A and B, Purdue Pegboard and Digit-Symbol Coding. Results Patients performed worse than HS on all tests (effect sizes from −0.88 to −1.73). Correlations with psychopathological dimensions were weak and involved reality distortion and disorganization. The duration of untreated psychosis (DUP) was not associated with cognitive impairment. Subjects living alone had a better neurocognitive performance, while the occupation status did not reveal any association with cognition. Conclusions A moderate/severe impairment of processing speed, motor dexterity, verbal memory and cognitive flexibility was found in the largest sample of FE patients analyzed so far. The impairment was largely independent from psychopathology and not associated with DUP.
The composite materials of CeO2 and ZnO (CeO2/ZnO) were prepared by one step hydrothermal method. The X-ray diffraction (XRD) patterns reveal that CeO2 does not enter the lattice of ZnO and no new phase is generated. The energy dispersive spectrometer (EDS) spectra of CeO2/ZnO demonstrates that the elemental composition on the surface of CeO2/ZnO is Ce, Zn, O. The scanning electron microscopy (SEM) images of CeO2/ZnO and pure ZnO show that the grain sizes of CeO2/ZnO significantly increased after compositing and part of CeO2 coating on the surface of ZnO. Tafel plot, cyclic voltammetry (CV), electrochemical impedance spectroscope (EIS) and galvanostatic charge–discharge measurements were utilized to examine the electrochemical performances of CeO2/ZnO. Compared with pure ZnO and ZnO physical mixed with CeO2 (ZMC), the CeO2/ZnO have a more positive corrosion potential in the zinc electrodes which indicates the CeO2/ZnO has a good anticorrosion ability. A lower charge platform and a flatter discharge platform of CeO2/ZnO indicate that the CeO2/ZnO have a better charge/discharge performance as anodic material for Ni/Zn cells. Most important of all, the CeO2/ZnO anodes show much more stable cycle stability. At the 50th cycle, the discharge capacity of pure ZnO anode reduces to 358.4mAhg−1 at 1C with the capacity retention ratio of 68%, while the capacity retention ratio of CeO2/ZnO anodes are 96.7%, 99.1% and 95.2%, respectively.
Mass/electron transports in a passive cathode of a proton exchange membrane (PEM) fuel cell have been studied numerically. The porous cathode in contact with a perforated current collector breathes fresh air through an array of orifices. Diffusions of reactant species in the porous cathodes are described by the Stefan–Maxwell equation. Electrochemical reaction on the surfaces of the porous cathode is depicted via the Butler–Volmer equation. Gas flow in the air-breathing porous cathodes is governed by isotropic linear resistance model with constant porosity and permeability. The electron/ion transports in the catalyst/electrolyte are dealt with the charge conservations based on the Ohm's law. A finite-element method is employed to solve the above-coupled equations. The effect of overpotential on the fluid flow, mass transport and electrochemistry is examined. Detailed electrochemical/mass characteristics such as flow velocities, species mass fraction, species flux and current density distributions are presented. They can provide a solid basis for optimizing the geometry of the PEM fuel cell stack running with a passive mode.
The capacity of pure LiFePO4 faded gradually from initial 149mAhg−1–117mAhg−1 under current density of 30mAg−1 at room temperature after 60 cycles. Some obvious cracks are observed in LiFePO4 particles after cycling. The formation of cracks would lead to poor electric contact and capacity fading. A possible mechanism is proposed for the appearance of the cracks.
Using a facile and effective method based on the solid phase reaction between Co(OH)2 and KBH4, we successfully synthesize orthorhombic CoB. It is shown that this CoB obtained is of high purity and thermal stability. A possible formation process for orthorhombic CoB is discussed in detail. In addition, crystalline CoB shows excellent electrochemical reversibility and considerable high charge–discharge capacities when it is used as the anode material for nickel-based secondary batteries. The reversible discharge capacities of the CoB electrode are found to be about 380mAhg−1 at a discharge current of 25mAg−1 and 360mAhg−1 at 100mAg−1. Moreover, electrochemical reaction mechanism of CoB is investigated in detail.
A novel doped activated carbon has been prepared from H2SO4-doped polyaniline which is prepared by the oxypolymerization of aniline. The morphology, surface chemical composition and surface area of the carbon have been investigated by scanning electron microscope, X-ray photoelectron spectroscopy and Brunaner–Emmett–Teller measurement, respectively. Electrochemical properties of the doped activated carbon have been studied by cyclic voltammograms, galvanostatic charge/discharge, and electrochemical impedance spectroscopy measurements in 6moll−1 KOH. The specific capacitance of the carbon is as high as 235Fg−1, the specific capacitance hardly decreases at a high current density 11Ag−1 after 10,000 cycles, which indicates that the carbon possesses excellent cycle durability and may be a promising candidate for supercapacitors.
In contrast to lithium-ion batteries where lithium ions carry the charge, a proton battery, making use of a hydrated Prussian blue analogue electrode, is shown to be able to transmit charges in the fashion of the Grotthuss mechanism, displaying ultrafast-rate and ultralong-life properties.
The effects of pulse charging technique on inner pressure and cycling characteristics of sealed Ni/MH batteries were investigated by comparison with the conventional direct current (DC) charging. The electrochemical impedance spectroscopy of cycled Ni/MH batteries have been measured. The micrographs of individual electrodes in the batteries have also been examined by SEM. Experimental results show that pulse charging is an effective approach to lower the internal pressure of battery during charge and overcharge, moreover, the appropriate frequency is t p = 5s and t n = 1s in our experiments. The battery charged by pulse current exhibits slower capacity fade rate and smaller overpotential at the same charge–discharge rate. In addition, the anode charged by pulse current exhibits less serious pulverization than that charged by DC charging. The possible explanation is that the short relaxation periods interspersed during the charging process can effectively eliminate the concentration polarization and increase the power transfer rate, thus accelerating the charging process, reducing the gas evolution reaction, slowing down the pulverization rate of electroactive materials and keeping the water absorption capability of separator constant.
The reactions in energy-optimized 25 Ah prismatic NMC/graphite lithium-ion cell, as a function of fast charging (1C4C), are more complex than earlier described. There are no clear charging rate dependent trends but rather different mechanisms dominating at the different charging rates. Ageing processes are faster at 3 and 4C charging. Cycling with 3C-charging results in accelerated lithium plating but the 4C-charging results in extensive gas evolution that contribute significantly to the large cell impedance rise. Graphite exfoliation and accelerated lithium inventory loss point to the graphite electrode as the source of the gas evolution. The results are based on careful post-mortem analyses of electrodes using: scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electrochemical impedance spectroscopy (EIS). SEM results show particle cracking independent of the charging rate used for the cycling. XPS and EIS generally indicate thicker surface film and larger impedance, respectively, towards the edge of the jellyrolls. For the intended application of a battery electric inner-city bus using this type of cell, charging rates of 3C and above are not feasible, considering battery lifetime. However, charging rates of 2C and below are too slow from the point of view of practical charging time.
In this paper, we mainly formulate the problem of predicting smartphone usage based on contextual information, which involves both the user-centric and device-centric contexts. In the area of mobile analytics, traditional machine learning techniques, such as Decision Trees, Random Forests, Support Vector Machines, etc. are popular for building context-aware prediction models. However, real-life smartphone usage data may contain higher dimensions of contexts and can be huge in size considering the daily behavioral data of the users. Thus, the traditional machine learning models may not be effective to build the context-aware model. In this paper, we explore “Mobile Deep Learning”, an artificial neural network learning-based model considering multiple hidden layers for predicting context-aware smartphone usage. Our model first takes into account context correlation analysis to reduce the neurons as well as to simplify the network model through filtering the irrelevant or less significant contexts, and then build the deep learning model with the selected contexts. The experimental results on smartphone usage datasets show the effectiveness of the model.
The structure and electrochemical performance of sodiated iron phosphate were investigated by means of X-ray diffraction, high-resolution transmission electron microscopy and electrochemical measurements. The results indicate that after the sodiation process, all FePO4 samples transform into the amorphous sodium iron phosphate and crystallite NaFePO4, namely triphylite NaFePO4 for amorphous FePO4 and maricite NaFePO4 for trigonal FePO4, respectively. The amorphous FePO4 samples show excellent electrochemical performance in terms of cyclic stability and discharge capacity, while trigonal FePO4 displays poor electrochemical performance. The outstanding electrochemical performance of amorphous FePO4 was attributed to the amorphous and triphylite NaFePO4 with high electrochemical activity. Those findings indicate that amorphous FePO4 can be transformed into active NaFePO4, which may have great potential as an electrode material for sodium-ion batteries.
Consequences after Traumatic brain injury (TBI) affect the injured person’s self-image and quality of life. The purpose was to assess the health related quality of life (HRQoL) at 12 months after a TBI in patients admitted to regional trauma centres, and to evaluate the metric properties of the Norwegian version of the Quality of Life After Brain Injury (QOLIBRI) questionnaire.