batterydata/paper-abstracts huggingface dataset:
Lithium iron phosphate (LFP) was prepared by hydrothermal synthesis in an organic-free system. Samples were collected at different time spots during temperature rising and soaking period and characterized by X-ray diffraction, scanning electron microscopy, B.E.T. specific surface area and particle size analysis. Two precursors, Li3PO4 and Fe3(PO4)2·8H2O, form easily at ambient temperature. They dissolve into ions once temperature increases to 135°C. LFP nuclei form rapidly at 135–140°C and grow fast at 140–150°C. The crystal morphology transforms from diamond to polygon plate at 150–160°C. The B.E.T. specific surface area and particle size decrease as reaction time prolongs. The thickness of the platelets remains unchanged within the range of 60–100nm for each LFP sample. The sample synthesized at 160°C for 2h and then coated with carbon (LFP/C-2) exhibits optimum electrochemical performances that the specific discharge capacities are 162.1, 150.8 and 136.9mAhg−1 at 0.2C, 1C and 5C, respectively. Reducing the precursors’ particle size would be an effective way to shorten the reaction time and obtain fine particles with high specific surface area and high purity.
LiNi0.5Mn0.5−x Ti x O2 series was prepared by a simple solid state method using MnO2, TiO2 and nickel carbonate basic as the starting materials. Its structural and electrochemical characteristics were also studied and compared with those prepared by the spray dry method. As Ti content increases, the degree of cation mixing increases and the structure of compound transforms gradually from a layered structure to a disordered rock salt structure. There are two plateaus in the initial charge curve for compounds with x < 0.3. One is around 4.0V and the other is around 4.6V. Both the initial charge and discharge capacities decrease as Ti content increases. Compounds with x < 0.3 exhibit good cyclic performance at room temperature.
This study first reports the synthesis of the nanosized LiVPO4F/graphene composite (LVPF/G). The LVPF/G composite is prepared by a facile mechanochemical approach. XRD results reveal that the prepared composite are well crystallized with triclinic LiVPO4F. SEM and TEM images demonstrate that the LiVPO4F nanoparticles in the composite are well enwrapped by graphene. Used as anode material for lithium ion batteries, the prepared LVPF/G composite exhibits greatly improved electrochemical performance. Furthermore, the electrochemical properties the LVPF/G composite depend heavily on the discharge cut-off potential. When the cut-off potential is altered to 0.01 V vs. Li/Li+, it possesses the best electrochemical performance. Under such optimal charge–discharge condition (3–0.01 V vs. Li/Li+), it shows an initial charge capacity of 287 mAh g−1 at 0.1C rate (1C = 310 mA g−1) and shows no capacity fading after 100 cycles. It also exhibits good rate capability, delivering about 168 mAh g−1 at 10C rate.
Graphite fluorides obtained by fluorination of graphite at room temperature and after a subsequent re-fluorination treatment were characterised by X-ray diffraction and 19F MAS NMR. Their electrochemical performances as cathode materials in magnesium batteries have been investigated. Four different electrolytes (0.5 or 1M Mg(ClO4)2 in ACN, DMSO, PC and THF) were used for these tests. The specific energy and power densities were estimated for all media. A comparison of the performances between lithium and magnesium batteries was realised. The effect, on the electrochemical performances, of a re-fluorination treatment at 250°C was also studied.
Triboelectric nanogenerator (TENG) is an emerging energy harvesting technology for potential charging solution of portable and wearable electronics. In previous studies, the designs of TENG have limitations to be used in portable applications due to the required size for contact-separation motion. In this work, we demonstrate portable self-retracting TENG (PSR-TENG) that can harvest mechanical energy through extraction and retraction process. The combination of stacking and fluttering motion during the extraction and retraction process generates multiple power peaks in a single input. Furthermore, the output of PSR-TENG is maximized by analyzing the motion of sheet dielectric and controlling the size dimensions of casing cylinder. Finally, for portable applications of PSR-TENG, we introduce pen-type TENG that have integrated PSR-TENG inside a hollow space of pen casing. This study is a potential solution for developing high power TENG, and utilizing TENG for stand-alone portable energy generators.
A 53-year old woman with tic doloureaux, affecting her right maxillary division of the trigeminal nerve (V2), could elicit shooting pains by slightly tapping her teeth when off medication. The pains, which she normally rated as > 6/10 on a visual analog scale (VAS), were electric shock-like in nature. She had no other spontaneous or ongoing background pain affecting the region. Based on her ability to elicit these tics, functional magnetic resonance imaging (fMRI) was performed while she produced brief shocks every 2 minutes on cue (evoked pain) over a 20 min period. In addition, she had 1–2 spontaneous shocks manifested between these evoked pains over the course of functional image acquisition. Increased fMRI activation for both evoked and spontaneous tics was observed throughout cortical and subcortical structures commonly observed in experimental pain studies with healthy subjects; including the primary somatosensory cortex, insula, anterior cingulate, and thalamus. Spontaneous tics produced more decrease in signals in a number of regions including the posterior cingulate cortex and amygdala, suggesting that regions known to be involved in expectation/anticipation may have been activated for the evoked, but not spontaneous, tics. In this patient there were large increases in activation observed in the frontal regions, including the anterior cingulate cortex and the basal ganglia. Spontaneous tics showed increased activation in classic aversion circuitry that may contribute to increased levels of anxiety. We believe that this is the first report of functional imaging of brain changes in tic-doloureaux.
To develop a hydrogen source for underwater applications, a composite of sodium borohydride and super absorbent polymer (SAP) is prepared by ball milling sodium borohydride powder with SAP powder, and by dehydrating an alkaline borohydride gel. When sodium polyacrylate (NaPAA) is used as the SAP, the resulting composite exhibits a high rate of borohydride hydrolysis for hydrogen generation. A mechanism of hydrogen evolution from the NaBH4–NaPAA composite is suggested based on structure analysis by X-ray diffraction and scanning electron microscopy. The effects of water and NiCl2 content in the precursor solution on the hydrogen evolution behavior are investigated and discussed.
The effects of fluorine substitution on the electrochemical properties of LiFePO4/C cathode materials were studied. Samples with stoichiometric proportion of LiFe(PO4)1−x F3x /C (x =0.025, 0.05, 0.1) were prepared by adding LiF in the starting materials of LiFePO4/C. XRD and XPS analyses indicate that LiF was completely introduced into bulk LiFePO4 structure in LiFe(PO4)1−x F3x /C (x =0.025, 0.05) samples, while there was still some excess of LiF in LiFe(PO4)0.9F0.3/C sample. The results of electrochemical measurement show that F-substitution can improve the rate capability of these cathode materials. The LiFe(PO4)0.9F0.3/C sample showed the best high rate performance. Its discharge capacity at 10C rate was 110mAhg−1 with a discharge voltage plateau of 3.31–3.0V versus Li/Li+. The LiFe(PO4)0.9F0.3/C sample also showed obviously better cycling life at high temperature than the other samples.
Graphene-based nano-materials have provided an opportunity for next-generation energy storage device, particularly for lithium–sulfur battery and sodium-ion battery (SIB), due to their unique properties. This review comprehensively summarizes the present achievements and the latest progress of inorganic nano-materials/graphene composites as the electrode materials for Li–S battery and SIBs. Electrochemical principles, performances and key obstructions of graphene-based materials in the actual application are considered. This review gathers and classifies updated knowledge about Li–S battery and SIB nanomaterials related to graphene, with the aim of offering a wide view of those systems. It is concluded that cost-effective SIBs and Li–S battery are promising next-generation battery candidates in the near future, but require further investigation and improvement to deal with some critical scientific issues.
Recent years have witnessed a thriving pursuit of high-energy Li metal batteries for replacing the existing Li-ion batteries. However, the cell chemistry involving extremely reactive Li metal anodes in flammable organic liquid electrolytes raises serious problems in battery performance and safety. Herein, we report on achieving high energy and superior safety in a quasi-solid-state rechargeable cell design in terms of Li metal-free stable redox chemistry between a Li2S cathode and Si anode in gel polymer electrolyte with favorable interfacial properties, ionic conductivity and robustness. This chemistry ensures intrinsically high safety even under extreme conditions by eliminating the uncontrolled exothermic chain reactions in the cells. A nanospace-confined bifunctional electrocatalytic adsorber is designed to minimize the diffusion restriction of the Li2S cathode in the gel electrolyte, while the Si anode is strengthened by a multilevel hollow design. The obtained quasi-solid-state rechargeable Li2S||Si full cells deliver a high specific energy of up to 802 W h kgLi2S+Si−1 with high durability, low self-discharge, and good temperature adaptability from −20 to 60 °C. Meanwhile, the cells exhibit excellent safety against mechanical damage, overheating and short circuit in the air or water, offering high reliability for practical use.
Composite polyethylene-oxide/garnet electrolytes containing LiTFSI as the lithium salt have a Li+ conductivity σLi > 10−4 Scm−1 at 55°C and a low plating/stripping impedance of a dendrite-free Li-metal anode; they have been developed for a safe solid-state Li-metal rechargeable battery. Composites consisting of “ceramic-in-polymer” to “polymer-in-ceramic” that are flexible and mechanically robust are fabricated by hot-pressing. Safe pouch cells with a remarkable flexibility have been fabricated. Solid-state LiFePO4 |Li batteries with electrolytes of “ceramic-in-polymer” and “polymer-in-ceramic” deliver excellent cycling stability with high discharge capacities (139.1mAhg–1 with capacity retention of 93.6% after 100 cycles) and high capacity retention (103.6% with coulombic efficiency of 100% after 50 cycles) at 0.2C and 55°C. Both kinds of electrolytes can be applied to solid-state lithium batteries.
The spinel-type Co3O4 with a dendritic nanostructure is prepared via homogeneous co-precipitation method in the presence of oxalic as complex agent. The special structure was characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis, which show that the precursor can be transformed into dendritic crystal Co3O4 by calcining at 500 °C for 2 h with a diameter of 20–50 nm. Such a three-dimensional interconnected structure used as an anode material for lithium-ion batteries shows that the discharge specific capacity still remains at 951.7 mA h g−1 after 100 cycles at a current density of 100 mA g−1. Furthermore, this material also presents a good rate performance; when the current density increases to 1,000, 4,000, and 8,000 mA g−1, the reversible capacity can render about 1,126.2, 932.3, and 344.2 mA h g−1, respectively. The excellent electrochemical performance is mainly attributed to the dendritic nanostructure composed of interconnected Co3O4 nanoparticles.
Employing “solid-state” mechanism can avoid polysulfides dissolution in lithium-sulfur batteries but lead to limited reactivity. It is desirable to eliminate polysulfides dissolution under “dissolution-deposition” mechanism but merely impossible with S8 due to its intrisic parasitic reaction pathway. However, sulfurized polyacrylonitrile (S@pPAN) is suggested to involve S3-4 and soluble intermediates Li2S3-4, thus a fast and reversible conversion to insoluble Li2S2 and Li2S can avoid dissolution. Herein, Te is used as eutectic accelerator in S@pPAN to accelerate the redox conversion and prevent polysulfides dissolution under “dissolution-deposition” mechanism. In TexS1-x@pPAN (Te-doped S@pPAN) cathodes, Te can be uniformly distributed through Te-S bond and accelerate the reactivity while contribute capacity, resulting in compatiblity with both ether and carbonate electrolytes, high capacities of 1507 and 861 mA h g−1 at 0.1 and 10 A g−1, and stable cyling over 600 cycles in ether electrolyte (0.05% decay per cycle). Good performance is also demonstrated with 3.11 mg cm−2 sulfur loading and 6 μL mg−1 electrolyte/sulfur ratio. Further studies confirm that Te promotes the diffusion of Li ion and reduces reaction resistance during charge/discharge process, which affords significantly enhanced reaction kinetics and mitigates polysulfides dissolution. This work shows a high performance lithium-sulfur batteries operated under “dissolution-deposition” without polysulfides dissolution.
Poly(3-chlorothiophene) (PCT) films were synthesized electrochemically by direct oxidation of 3-chlorothiophene (CT) in mixed electrolytes of boron trifluoride diethyl etherate (BFEE) and trifluroacetic acid (TFA). The oxidation potential of 3-chlorothiophene in pure BFEE was measured to be only 1.54 V versus SCE. This value is much lower than that determined in neutral medium (2.18 V vs. SCE). The addition of TFA to BFEE can further decrease the oxidation potential of the monomer. The oxidation potential of CT in the mixed electrolyte of BFEE containing 30% TFA (by volume) was found to be as low as 1.16 V (vs. SCE). PCT films with the highest quality were obtained from the media of BFEE+10–15% TFA and they were characterized to have about 24–32 repeat units. The doping level and conductivity of PCT films also increased significantly by using the mixed electrolytes.
A series of Ni substituted spinel LiNi x Mn2−x O4 (0≤ x ≤0.5) have been synthesized to study the evolution of the local structure and their electrochemical properties. X-ray diffraction showed a few Ni cations moved to the 8a sites in heavily substituted LiNi x Mn2−x O4 (x ≥0.3). X-ray photoelectron spectroscopy confirmed Ni2+ cations were partially oxidized to Ni3+. The local structures of LiNi x Mn2−x O4 were studied by analyzing the F 2 g ( 1 ) and A1g Raman bands. The most compact [Mn(Ni)O6] octahedron with the highest bond energy of Mn(Ni)O was found for LiNi0.2Mn1.8O4, which showed a Mn(Ni)O average bond length of 1.790Å, and a force constant of 2.966Ncm−1. Electrolyte decomposition during the electrochemical charging processes increased with Ni substitution. The discharge capacities at the 4.1 and 4.7V plateaus obeyed the linear relationships with respect to the Ni substitution with the slopes of −1.9 and +1.9, which were smaller than the theoretical values of −2 and +2, respectively. The smaller slopes could be attributed to the electrochemical hysteresis and the presence of Ni3+ in the materials.
Classification of renal cell carcinomas has become more challenging. The 2016 WHO classification included 14 different subtypes and 4 emerging/provisional entities, and recent literature indicates new entities to be incorporated. Nomenclature is based on cytoplasmic appearance, architecture, combination of morphologies, anatomic location, underlying disease, familial syndromes, and specific genetic alterations. Immunohistochemistry is useful in selected cases while it can be insufficient in entities that require molecular confirmation of a specific gene alteration. The aim of these recommendations is to provide a reasonable and optimized approach for the use of ancillary tests in subtyping renal tumors, particularly in resource-limited settings.
Silicon is considered one of the most promising anode materials for next-generation lithium-ion batteries. However, dramatic volume expansion during the lithiation of silicon complicates its practical implementation. Literature reports nanostructured electrodes, which are capable to accommodate the volume expansion, reducing associated swelling, degradation and capacity fading. However, several phenomena associated with the volume expansion, such as the reduction of the electrode’s porosity, are inherent to the system and must be carefully considered for targeted engineering of high-energy lithium-ion batteries. Herein, we determine design criteria of silicon based electrodes, taking into account the volume expansion during lithiation. A “deformation threshold” is defined signifying the minimum value of the initial porosity that must be adjusted to avoid plastic deformation and dramatic reduction of the electrode’s porosity during charging. In addition, a “C-rate threshold” is defined, guaranteeing diffusion limited currents not falling below a desired discharge rate. The impact of these theoretical limitations on the electrochemical performance of silicon-based electrodes is analyzed from an engineering point of view. The derived relations are used to optimize the electrode design parameters regarding maximum gravimetric and volumetric capacity.
Cribrostatin 6 is a quinone-containing natural product that induces the death of cancer cell lines in culture, and its mechanism of action and scope of activity are unknown. Here we show that cribrostatin 6 has broad anticancer activity, potently inducing apoptotic cell death that is not preceded by any defined cell cycle arrest. Consistent with this data, we find that cribrostatin 6 treated cells have large amounts of reactive oxygen species (ROS) and, based on transcript profiling experiments and other data, this ROS generation is likely the primary mechanism by which cribrostatin 6 induces apoptosis. Given the success of certain ROS producers as anticancer agents, cribrostatin 6 has potential as a novel chemotherapeutic agent.
In order to perform an in-depth study on the electropolymerization mechanism of bis(alkyl)-substituted bithiophenes, poly[4,4′-bis(metylbutylthio)-2,2′-bithiophene] (poly-MBTBT) has been electrogenerated by using both potentiodynamic and potentiostatic techniques under different experimental conditions. Bidimensional spectroelectrochemical data have allowed us to obtain valuable information about both the polymer and the soluble oligomers electrogenerated in the process. The same kind of oligomers has been observed in the potentiodynamic and potentiostatic polymerization.
This paper proposes a new Peak Shaving algorithm in combination with a continuous battery peak power estimation algorithm for a battery energy storage system (BESS). The objective of the proposed Peak Shaving algorithm is to avoid energy exchanges when the output power is considered to be too high. Therefore, the algorithm allows configuring the power limits for the system operation. However, in extreme situations, the BESS might no longer be able to follow the algorithm commands and the power will surpass this limit. In these situations, the proposed dynamic minimum voltage tracking algorithm ensures that the maximum available power is extracted from the BESS, thus reducing the total output power. The proposed control system has been experimentally tested on a real-time microgrid. Results show that the proposed Peak Shaving algorithm allows to easily limit power exchanges between the microgrid and the main grid. Moreover, combining it with the dynamic minimum voltage tracking algorithm ensures that the power surplus, with reference to the defined limit, is minimized.
Hierarchical porous cobalt oxide (Co3O4) array films are successfully prepared by electrodeposition through polystyrene sphere monolayer template. The as-prepared Co3O4 array films exhibit three typical porous structures from non-close-packed bowl array to close-packed bowl array and hierarchical two layer array structures. These Co3O4 array films have a hierarchical porous structure, in which the skeleton is composed of ordered arrays possessing nanoporous walls. A possible growth mechanism of porous Co3O4 array films is proposed. As anodes for Li ion batteries, the as-prepared Co3O4 array films exhibit quite good cycle life and high capacity. The first discharge capacity for the three Co3O4 array films is 1511, 1475, 1463mAhg−1, respectively, and their initial coulombic efficiencies are as high as 72%. The specific capacity after 50 cycles for the three electrodes is 712, 665 and 640mAhg−1 at 1C rate, corresponding to 80%, 75%, 72% of the theoretical value (890mAhg−1), respectively.
Publisher Summary Ubiquitous computing user experiences come in all shapes and sizes. With computation distributed into mobile devices, buildings, and roads, the experience of devices and spaces is no longer limited to what can be held, seen, or inhabited. This presents a fundamental challenge to assumptions that designers are only responsible for scoping interaction at single scales with single objects. Certainly some designers and some designs try to consider a device or interaction in context of the other devices, spaces, and networks it touches. But situating the design of user experience within ecology of spaces, devices, and audiences from small to large scales of interaction has never been necessary. Though scale fundamentally affects the user experience, there are few guidelines for designing at different scales. Interior design has focused on body-scale experiences, interface design has (largely) focused on design for computer monitors, and industrial design has focused on how hands manipulate objects. No one discipline teaches a design framework that covers the continuum of all the scales of interaction in our immediate live environment.
In this paper, Cu, Al and Ni were plated on the AB5–5mass% LaMg3 composite hydrogen storage alloy using a vacuum evaporation plating method. The phase structure and the electrochemical properties were investigated. The X-ray diffraction (XRD) analysis shows that the phase structure is not changed obviously after the plating Cu, Al and Ni on the composites. The electrochemical tests show that maximum discharge capacity, high rate dischargeability (HRD), dischargeability at low temperature and cyclic stability was improved by vacuum evaporation plating Cu, Al and Ni. Maximum of discharge capacity of the AB5–5mass% LaMg3 composite alloy plating Ni can reach 351mAh/g, which is 3.5% higher than that of the untreated. HRD at I d =1200mA/g of the composite alloy plating Cu is 45.0% of that at 60mA/g, which is 20.4% higher than the untreated. Discharge capacity of the composite alloy plating Cu at low temperature 233K is 205mAh/g, which is 57.3% of that at 298K, and it is much higher than 36.8% of the untreated composites. The discharge capacity retention of the composite alloy plating Al after 200 cycles is 7.8% higher than the untreated.