batterydata/paper-abstracts huggingface dataset:
Molybdenum disulfide (MoS2) has been considered as a promising anode material for sodium-ion batteries. But the low electronic conductivity and large volume change during sodiation/desodiation processes limit its wide application. In the present study, a single-layer MoS2 embedded in amorphous carbon nanofibers is fabricated by electrospinning. The obtained MoS2/carbon nanofibers have unique hierarchical structure incorporating 2D single-layer ultrasmall MoS2, 1D carbon continuous phase and 3D interconnected porous network. When employed as anode material in sodium-ion battery, this hierarchical structure can enlarge accessible surface area of MoS2, accelerate ion diffusion speed, shorten ion transfer length and improve the bulk conductivity, and then endow MoS2/carbon nanofibers composite with high capacity and superior cycling stability. The electrochemical results show that the initial discharge and charge capacities of MoS2/carbon nanofibers can reach 921 and 665mAhg−1. After repeated charge-discharge test for 100cycles, a stable capacity of 485mAhg−1 is achieved, demonstrating a very low capacity loss of 0.05% per cycle.
Silicon is a highly promising anode material of lithium ion batteries (LIBs) for its low insertion voltage and high reversible capacity. A flexible, honeycomb-like film of reduced graphene (RGO)/Si nanoparticles (NPs) composite with a thickness as thick as 25μm is synthesized by a facile vacuum filter assembly process. The Si NPs are enwrapped into the RGO sheets with an areal density of 0.65mgcm−2. The ultra-thick composite film is directly employed as an anode for LIBs without using any binder and conductive additive. The flexible RGO sheet coat enables the electrode to maintain the structural integrity and provide continuous conductive paths for Si NPs. The electrode exhibits a high capacity of 2370mAhg−1 over 50 cycles at a current of 210mAg−1 and a capacity higher than 1000mAhg−1 at a current density of 4200mAg−1 after 500 cycles. Especially, the electrode exhibits excellent rate capability, indicating that it may be applied to the high-power LIBs as a flexible, high areal capacity, binder-free and free-standing anode.
Supercapacitors with high capacitance, high energy density and a small time constant have been developed successfully using functionalized activated carbon nanoparticles (FACNs) and a cross-linkable polymeric binder in neutral aqueous Na2SO4. Due to the functional groups on the FACNs’ surface and the slenderness of the FACNs’ nanocomposite electrode, the FACNs’ nanocomposite electrode exhibits superior specific capacitance of 154F/g, energy density of 18Wh/kg, and a time constant of 0.25s. Furthermore, the cyclic voltammogram is still rectangular in shape even at exceedingly high scan rates of 5V/s. These characteristics show that our proposed method is suitable for the fabrication of high-performance supercapacitors.
New electrolyte solutions based on ternary and quaternary solvent mixtures containing significant amounts of toluene (tol) have been evaluated. Liquid electrolytes containing LiAsF6 and LiPF6 exhibit electrolytic conductivities >1 S cm−1 down to −50°C. When incorporated into PVDF host matrixes, these multicomponent solutions exhibit reduced conductivities but still remain sufficiently high, yielding useful conductivities down to at least −40°C. LiC6/PVDF-electrolyte/LiCoO2 cells containing these multicomponent electrolyte solutions are stable and highly reproducible. Ambient temperature performance is essentially equal to comparative LiC6/PVDF/LiCoO2 cells containing ternary mixtures such as ethylene carbonate (EC):dimethyl carbonate (DMC):diethyl carbonate (DEC) and EC:ethylmethyl carbonate (EMC):DMC; but at −20°C, −30°C and −40°C, cells containing the quaternary mixed solvent EC:EMC:methyl acetate (MA):tol are clearly superior. Capacity retention of cells utilizing this quaternary solvent in PVDF at −40°C is 50% of nominal capacity at ambient temperatures.
The second plateau occurring during the reduction of the nickel oxyhydroxide electrode (NOE) was studied by impedance spectroscopy on a cell with a pasted electrode prepared from commercial undoped β-Ni(OH)2. Measurements were performed at diverse states of reduction and a large variation of impedance upon the transition from the first to the second plateau was observed. This variation mainly takes place at low frequencies and is hence related to ionic diffusion. We observed that the impedance becomes more capacitive on the second plateau meaning that the proton diffusion is limited. These results would be consistent with the gradual formation of an insulating layer of nickel hydroxide at the interface between the NOE and the electrolyte upon reduction. Once this layer becomes compact the ionic diffusion would be hindered and forced to occur through this layer, which could explain the voltage drop observed.
works as Composite Design Engineer and is responsible for the technical composite lab to build drones at the Southern University of Denmark SDU in Odense (Denmark). Previously, he led the Composite Developments of SPIRI ApS in Kopenhagen (Denmark).
Objective: To assess the relationship between cerebellum and brain cortical activity without motor factors, we recorded the mid-latency auditory evoked responses (MLRs) with simultaneous recording of the electroencephalography (EEG) at rest in patients with ‘pure cortical cerebellar atrophy (CCA)’. Methods: We studied 12 normal control subjects and non-demented ‘pure CCA’ patients determined by quantitative magnetic resonance imaging analysis. A comprehensive neuropsychological test battery assessed intelligence, frontal lobe function and word fluency. Spontaneous eyes-closed resting EEG and MLRs were recorded from 20 scalp electrodes and analysed with low-resolution electromagnetic tomography (LORETA) to compute the 3-dimensional intracerebral distribution of electric activity. Results: Neuropsychological tests revealed no differences between CCA and the control. Analysis of EEG and MLRs using classical methods also did not reveal any differences. LORETA analysis indicated significant decrease of alpha2 activity in the left inferior frontal gyrus in CCA. On MLRs, the most significant difference was observed at P1 component, and CCA patients showed significant decrease at the right superior frontal gyrus. Conclusions: Our results indicated that the frontal lobe and ascending reticular activating system are inhibited in CCA patients, and suggested the involvement of the cerebellum in cortical electric activities irrespective of motor adjunct. Significance: Quantitative EEG and MLR measurements with LORETA pointed out frontal lobe hypoactivities in pure CCA patients.
The United States Food and Drug Administration (FDA) are currently producing guidelines for the scientific adequacy of patient reported outcome measures (PROMs) in clinical trials, which will have implications for the selection of scales used in future clinical trials. In this study, we examine how the Cervical Dystonia Impact Profile (CDIP-58), a rigorous Rasch measurement developed neurologic PROM, stands up to traditional psychometric criteria for three reasons: 1) provide traditional psychometric evidence for the CDIP-58 in line with proposed FDA guidelines; 2) enable researchers and clinicians to compare it with existing dystonia PROMs; and 3) help researchers and clinicians bridge the knowledge gap between old and new methods of reliability and validity testing.
The aim of this study was to evaluate the clinical performance of adhesive filling materials in class V cavities in xerostomic head- and neck-irradiated cancer patients, in terms of marginal adaptation, anatomical form and recurrent caries. We selected 35 high-caries-risk, post-radiation, xerostomic adults with ≥3 cervical carious lesions in the same arch. Every patient received a KetacFil (KF), PhotacFil (PF) and Herculite XRV (HX) restoration. Patients were instructed to use a neutral 1% sodium fluoride gel in custom trays, on a daily basis. After 6, 12, 18 and 24 months, the restorations were examined for material loss, marginal integrity and recurrent caries. Fluoride compliance was determined at each recall appointment and recorded as the percentage of recommended use during that interval [compliance of ≤50% = NFUs, >50% = FUs]. Only 30 patients were available for recall at 6 months, with 28 patients at 12 and 18 months, and 27 patients at 24 months. In the NFU group, differences in recurrent caries were found between KF and HX at all observation times (p < 0.05). Differences (p < 0.05) in adaptation and/or anatomical form were found between KF and PF in NFUs after 18 and 24 months. In FUs, significant differences were observed between KF and PF, and KF and HX after 6 and 12 months, between KF and HX, PF and HX after 18 and 24 months. In summary, glass ionomers (especially the conventionally setting formulation) provide clinical caries inhibition but erode easily, while composite resin provides greater structural integrity.
One-dimensional (1D) ZnCo2O4 porous nanotubes (PNTs) have been synthesized using a simple technique of electrospinning followed by calcination in air and firstly applied in supercapacitors (SCs). The obtained ZnCo2O4 nanomaterial displays 1D architecture with a highly porous nature and hollow interiors. This unique structure significantly enlarged the electroactive surface areas of the ZnCo2O4, leading to better electrolyte/electrode contact, more efficient transport pathways and good strain accommodation. Our experimental results demonstrate that it exhibits a high specific capacitance of 770 F g−1 at 10 A g−1, excellent rate property (84% of the capacity retention at 60 A g−1) and good cycling stability of only 10.5% loss after 3000 cycles. Compared with the ZnCo2O4 nanoparticals, such obtained PNTs possess enhanced rate and capacitive properties. Our work conﬁrms the as-prepared ZnCo2O4 PNTs can serve as advanced SCs materials. It is highly expected this simple method of electrospinning can be extended to prepare other superior electrochemical materials.
An essential way to enhance the energy density of a supercapacitor(SC) is to use high capacitance electrode materials via developing binder-free electrode with porous and hierarchical nanostructures. Herein, we demonstrated the use of copper antimony sulfide (Cu3SbS4) nanowires directly grown on Ni foam (using a microwave-irradiation process) as a binder-free positive electrode for SCs. The growth mechanism, effect of microwave irradiation time on the morphology and electrochemical properties of Cu3SbS4 on Ni foam were discussed in detail. The cyclic voltammetric studies (using three-electrode test) of Cu3SbS4/Ni-5 electrode showed the presence of Type-C battery-like charge-storage properties. The Cu3SbS4/Ni-5 electrode delivered a high specific capacity (835.24 mA h g−1) as obtained from the charge-discharge analysis (at a current density of 2.5 mA cm−2). Further, the device specific properties of the Cu3SbS4/Ni-5 positive electrode was examined via fabricating asymmetric supercapacitors (ASCs) using two different negative electrodes viz. (i) planar-graphene, and (ii) binder-free copper molybdenum sulfide anchored on Ni foam (Cu2MoS4/Ni) electrodes, respectively. The electrochemical analyses of the fabricated ASCs revealed that the Cu3SbS4/Ni-5║Cu2MoS4/Ni ASC possess almost 3.0-fold higher energy density compared to the Cu3SbS4/Ni-5║graphene ASC. The Cu3SbS4/Ni-5║Cu2MoS4/Ni ASC delivered a high specific device capacitance of 213.6 F g−1 with a remarkable energy density (58.15 Wh kg−1), maximum power density (6363.63 W kg−1), and better cycle-life. The use of two different binder-free electrodes in the Cu3SbS4/Ni-5║Cu2MoS4/Ni ASC results in their superior performance metrics over the reported ASCs, thus, highlighting their potential applications towards next-generation supercapacitors.
The effectiveness of electrolyte additives in fluorinated electrolytes containing 1 M LiPF6/fluoroethylene carbonate:bis (2,2,2-trifluoroethyl) carbonate (1:1 w:w) were studied in high voltage Li(Ni0.4Mn0.4Co0.2)O2/graphite pouch cells tested to 4.5 V. The results showed that fluorinated electrolytes containing prop-1-ene-1,3-sultone alone or in combination with other additives exhibited significant improvements in terms of coulombic efficiency and charge endpoint capacity slippage during UHPC cycling, voltage drop during storage, as well as capacity retention during long-term cycling compared with state-of-the-art ethylene carbonate-based (ethylene carbonate: ethylmethyl carbonate 3:7) or sulfolane-based electrolytes (sulfolane: ethylmethyl carbonate 3:7) with some promising additive blends. These results indicate that fluorinated electrolytes offer an interesting alternative for high voltage Li-ion batteries.
ABSTRACT Background Adjunctive techniques that may facilitate the early detection of oral premalignant and malignant lesions (OPML) have emerged in the past decades. Methods The authors undertook a systematic review of the English-language literature to evaluate the effectiveness of toluidine blue (TB), ViziLite Plus with TBlue (Zila Pharmaceuticals, Phoenix), ViziLite (Zila Pharmaceuticals), Microlux DL (AdDent, Danbury, Conn.), Orascoptic DK (Orascoptic, a Kerr Company, Middleton, Wis.), VELscope (LED Dental, White Rock, British Columbia, Canada) and OralCDx (Oral CDx Laboratories, Suffern, N.Y.) brush biopsy. They abstracted data relating to study design, sampling and characteristics of the study group, interventions, reported outcomes and diagnostic accuracy of adjunctive aids from 23 articles meeting inclusion and exclusion criteria, including availability of histologic outcomes. Results The largest evidence base was for TB. A limited number of studies was available for ViziLite, ViziLite Plus with TBlue and OralCDx. Studies of VELscope have been conducted primarily to assess the margins of lesions in known OPML. The authors identified no studies of Microlux DL or Orascoptic DK. Study designs had various limitations in applicability to the general practice setting, including use of higher-risk populations and expert examiners. Conclusions There is evidence that TB is effective as a diagnostic adjunct for use in high-risk populations and suspicious mucosal lesions. OralCDx is useful in assessment of dysplastic changes in clinically suspicious lesions; however, there are insufficient data meeting the inclusion criteria to assess usefulness in innocuous mucosal lesions. Overall, there is insufficient evidence to support or refute the use of visually based examination adjuncts. Practical Implications Given the lack of data on the effectiveness of adjunctive cancer detection techniques in general dental practice settings, clinicians must rely on a thorough oral mucosal examination supported by specialty referral and/or tissue biopsy for OPML diagnosis.
Vast improvement of the capacitance of supercapacitors without sacrificing high power density and cycle performance brings bright application prospect. Here, a novel cobalt hexacyanoferrate/multi-walled carbon nanotubes (CoHCF/MWCNTs) nanocomposite is prepared by a simple and facile approach and further investigated as electrode materials for supercapacitors. The physical properties of as-prepared materials are characterized by XRD, FTIR, Raman and FE-SEM techniques. Furthermore, electrochemical performances of as-prepared materials are investigated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy in 1.0 M Na2SO4 electrolyte. It is shown that as-prepared CoHCF/MWCNTs (25.0 wt% of MWCNTs) nanocomposite based electrode exhibits the best electrochemical performances, including higher specific capacitance/capacity (648.5 F g−1/810.6 C g−1 at 1.4 A g−1), good rate capability (648.5 F g−1/810.6 C g−1 and 436.3 F g−1/545.3 C g−1 at 1.4 A g−1 and 15 A g−1, respectively) and excellent cycling stability (94.3% capacitance retention after 3000 cycles at 2.0 A g−1) in all as-prepared electrodes. The results demonstrate that as-prepared CoHCF/MWCNTs nanocomposite is a promising candidate for electrochemical energy storage.
Cognitive deficits are documented in first-episode psychosis (FEP), but the continuing course is not fully understood. The present study examines the longitudinal development of neurocognitive function in a five year follow-up of FEP-patients, focusing on the relation to illness severity, as measured by relapses and diagnostic subgroups. The study is an extension of previous findings from the TIPS-project, reporting stability over the first two years. Sixty-two FEP patients (53% male, age 28±9years) were neuropsychologically examined at baseline and at 1, 2, and 5year follow-ups. The test battery was divided into five indices; Verbal Learning, Executive Function, Impulsivity, Motor Speed, and Working Memory. To investigate the effect of illness severity, the sample was divided in groups based on number of relapses, and diagnostic subgroups, respectively. Impulsivity and Working Memory improved significantly in the first two years, followed by no change over the next three years. Motor Speed decreased significantly from 2 to 5years. Number of relapses was significantly related to Verbal Learning and Working Memory, showing a small decrease and less improvement, respectively, in patients with two or more episodes. No significant association was found with diagnostic group. Neurocognitive stability as well as change was found in a sample of FEP-patients examined repeatedly over 5years. Of potential greater importance for understanding how psychotic illnesses progress, is the finding of significant associations between neurocognition and number of relapses but not diagnostic group, indicating that neurocognition is more related to recurring psychotic episodes than to the descriptive diagnosis per se.
The local structure refinement for the chemically Li-ion extracted LiNi1− x Al x O2 system has been intensively carried out with Ni K-edge and O K-edge X-ray absorption spectroscopy. The Li-ion extraction gives rise to the substantial variation of unit cell dimension, which presents the systematic decrease of lattice parameter a and the increase of lattice parameter c. For Ni K-edge XANES spectra, the strong absorption peak by ligand to metal charge transfer (LMCT) process represents that the electronic configuration of Ni ion in the ground state is located in the equilibrium between Ni3+(t2g 6eg 1) + O2− (2p6) ↔ Ni2+(t2g 6eg 2) + O− (2p5). The Li-ion extraction leads to the peak shift towards higher energy region and particularly the systematic decrease of peak intensity for the LMCT process, which is due to the dominant formation of Ni3+ O2− ion pair by the transfer of hole state (L) in the oxygen 2p band to the Ni atomic site. For EXAFS refinement, the separated FT peak by Jahn–Teller distorted NiO6 octahedra becomes a symmetric feature of regular oxygen distribution on the extraction. The average interatomic distances of NiO and NiNi bonds decrease systematically, meaning the formation of more covalent Ni3+ O2− character. From oxygen K-edge spectra, furthermore, it is found out that the charge compensation for the electron exchange can be achieved at oxygen site as well as Ni site.
Daily exposure to PM2.5 in developing countries has not been thoroughly studied partly due to limited resources available. In this research, personal PM2.5 exposures in urban communities in Indonesia were examined using a low-cost sensor, AS-LUNG. Fifty subjects were recruited in both wet and dry seasons. Their personal PM2.5 concentrations, environmental temperature, and relative humidity were measured using corrected AS-LUNG Portable worn or placed in their vicinity. Details on their activities and locations, air quality (air pollution sources), and weather conditions during monitoring were recorded in time-activity diaries completed at 30 min intervals. Results revealed mosquito coil burning as the source of highest exposure, reaching 241.5 μg/m3 but with significant difference between wet and dry seasons. With ambient PM2.5 and relative humidity controlled for, mosquito coil burning contributed 12.02 μg/m3 and 4.84 μg/m3 of personal PM2.5 exposure in wet and dry season, respectively, which was several times higher than the contribution from vehicle emission. The second most contributive source was factory smoke, which increased 4.99 μg/m3 and 3.17 μg/m3 of exposure in wet and dry season, respectively. Findings on contributive factors of high daily personal exposures can serve as useful references for formulating policies and recommendations on exposure reduction and health protection.
Capsule endoscopy has recently been introduced to explore endoscopically the whole small intestine, fulfilling a gap between examinations of the upper and lower gastrointestinal tract. The technique consists of a miniaturized endoscope, embedded in a swallowable capsule that is propulsed by peristalsis and achieves the journey to the right colon in five to eight hours. Images captured by the capsule are recorded on a hard drive worn in a belt by the patient. The main indication for capsule examination is the examination of the small bowel to find a bleeding lesion in patients with obscure bleeding. Several studies have shown that the diagnostic yield of capsule endoscopy is superior to that of push enteroscopy in this indication. Other possible indications are patients with suspected intestinal location of Crohn's disease, familial adenomatous polyposis, complicated coeliac disease and lesions due NSAIDs. The review contains information on the technical aspects of capsule endoscopy and discusses the indications. Issues of safety and tolerance are also discussed.
The addition of supplementary carbon to lead–acid batteries that are intended for use in emerging automotive duties can provide improvement in two aspects of performance. (i) In both hybrid electric and battery electric vehicles that are designed to preserve energy through the operation of regenerative-braking, conventional lead–acid batteries exhibit a rapid decline in the efficiency of the recuperative charging (which can involve rates up to 30C1 ) and fail quickly as a result of an accumulation of lead sulfate on the negative plate. It has been widely reported that supplementary carbon — either intimately mixed with the negative active-material or included as a separate component attached to the plate — can enhance charge-acceptance. (ii) Full-hybrid electric and battery electric vehicles employ high-voltage batteries composed of large numbers of cells connected in series. Consequently, when conventional lead–acid batteries are used in such configurations, the continuous cycling encountered in normal driving will almost certainly lead to divergence in the states-of-charge of the unit cells and thereby demand periodic equalization charges. In this application, it has been demonstrated that lead–acid batteries with supplementary carbon incorporated into the negative plate are rendered immune to the divergence problem and therefore operate without the need for an equalization charge. The inclusion of supplementary carbon does, however, promote hydrogen evolution and failure due to the loss of water from the electrolyte solution. Current research efforts are directed towards methods by which this disadvantage can be mitigated without losing the benefits that the addition of carbon provides. This review covers the extensive research that has been conducted to understand the mechanism by which the additional carbon operates, the additional studies that have sought to identify the best types and optimum amounts of carbon that should be used, together with the most effective manner for their deployment.