batterydata/paper-abstracts huggingface dataset:
MoO2/C nanocomposite has been prepared by simultaneously reducing as-prepared MoO3 nanosheets and introducing an amorphous carbon matrix in the combination of facile hydrothermal and post-annealing processes. MoO2 nanoparticles are uniformly embedded in the carbon framework, resulting in porous nanostructured MoO2/C composite material. The MoO2/C electrodes exhibit varied electrochemical working mechanisms for sodium ion storage that is dependent on charge/discharge rates. At low charge/discharge rate conditions, MoO2/C nanocomposite shows dominant battery performances for sodium ion storage involving reversible conversion reaction of MoO2. The MoO2/C anode material can deliver high initial charge capacity of 557.2mAh/g at 0.1C (1C =600mA/g), along with good cycling stability in comparison with bare MoO2 material. At high rate situations, cyclic voltammetric (CV) results indicate distinct pseudocapacitive behaviors of MoO2/C materials when the scanning rate is higher than 0.5mV/s. Specific capacitances of 123.25, 85.47 and 49.90F/g can be obtained from CV measurements conducted at 1, 2 and 5mV/s, respectively. These electrochemical performances illustrate remarkable capabilities of MoO2/C nanocomposite as anode material for sodium ion storage involving varied conversion reactions and pseudocapacitive sodiation/desodiation reactions depending on charge/discharge rates.
Unsustainable and inefficient capacitive deionization (CDI) performance has been observed through CDI operation with carbon xerogel (CX) electrodes for 50 hours using a constant-voltage charging method. This behavior is primarily accounted for by changes in the surface chemistry for the studied material via oxidation of the carbon electrodes in an aqueous solution. In order to improve performance stability, we have developed a novel CDI system using an anode with net negative surface charges and a cathode with net positive surface charges. As a result, salt separation in this system is achieved in an opposing manner to the conventional CDI system, e.g., when the system is charged using a power source, cations and anions are desorbed at the anode and cathode, respectively. This system is named the inverted capacitive deionization (i-CDI) system. Most importantly, salt separation in the i-CDI system was maintained for over 600 hours, which is approximately an increase of 530% in lifetime compared to a CDI system operated under similar conditions. This enhanced performance stability is attributed to the use of oxidized anodes in the i-CDI system, which limits the possibility for loss in separation performance due to carbon oxidation in an aqueous solution.
With focus on mobile applications a fuel cell auxiliary power unit (APU) using liquefied petroleum gas (LPG) is currently being developed at the Centre for Fuel Cell Technology (Zentrum für BrennstoffzellenTechnik, ZBT gGmbH). The system is consisting of an integrated compact and lightweight fuel processor and a low temperature PEM fuel cell for an electric power output of 300W. This article is presenting the current status of development of the fuel processor which is designed for a nominal hydrogen output of 1 k W th , H 2 within a load range from 50 to 120%. A modular setup was chosen defining a reformer/burner module and a CO-purification module. Based on the performance specifications, thermodynamic simulations, benchmarking and selection of catalysts the modules have been developed and characterised simultaneously and then assembled to the complete fuel processor. Automated operation results in a cold startup time of about 25min for nominal load and carbon monoxide output concentrations below 50ppm for steady state and dynamic operation. Also fast transient response of the fuel processor at load changes with low fluctuations of the reformate gas composition have been achieved. Beside the development of the main reactors the transfer of the fuel processor to an autonomous system is of major concern. Hence, concepts for packaging have been developed resulting in a volume of 7l and a weight of 3kg. Further a selection of peripheral components has been tested and evaluated regarding to the substitution of the laboratory equipment.
Flower shaped nanostructures of an architypical transparent conducting oxide, SnO2, have been synthesized by an electrospinning technique for the first time by precisely controlling the precursor concentration in a polymeric solution. The flowers were made up of nanofibrils of diameter ∼70–100 nm, which in turn consisted of linear arrays of single crystalline nanoparticles of size 20–30 nm. Mott–Schottkey analysis shows that flowers have an order of magnitude higher electron density compared with the fibers despite their chemical similarity. Dye-sensitized solar cells fabricated using the flowers showed a record open circuit voltage of ∼700 mV and have one of the highest photoconversion efficiencies so far achieved with SnO2 and the iodide/triiodide electrolyte. The photoaction spectra and impedance spectroscopic measurements show that the flowers are characterized by a higher electron lifetime, owing to their enhanced crystallinity, compared to the conventional fibrous structure.
Different types of graphite materials, i.e. synthetic graphite flakes and natural graphite flakes which are used as anode materials in Li-ion batteries were studied. Differences in the electrochemical behavior of electrodes comprised of these materials, mainly in their irreversible capacity, could be correlated to the differences in the particle morphologies and their crystal structure. We propose that graphite particles with a large amount of crevices in their edge planes can crack, due to a build-up of internal pressure as a result of reduction of solution species on the carbon surfaces during the first cathodic polarization on the electrodes. Another important factor determining the electrodes’ stability is the existence of some disorder in the particles’ structure.
We introduce a handheld single-fiber laser-scanning confocal microscope, incorporating a high-reflectivity two-axis silicon vertical combdrive microscanner, aimed at in vivo early detection of epithelial precancers. The approach adopted is motivated by need for a portable, economical, biopsy-free, early precancer screening technology in low-infrastructure environments. Our microelectromechanical system (MEMS) based handheld probe integrates the microscanners with miniature objective lens system and flexible electrical routing in a forward-imaging configuration, with 4.8 mm distal probe tip outer diameter for unrestricted imaging access in biological sites such as the oral cavity and cervix. Reflectance confocal videos of a USAF 1951 resolution target and biological samples were obtained over 200 μm × 110 μm field of view, with 0.80 and 9.55 μm lateral and axial resolution, at 3.5–5.0 frames per second. With improvements to objective numerical aperture, our probe can enable precise evaluation of nuclear size, density, nucleus-to-cytoplasm ratio and cell density, which are important visual identifiers of epithelial precancers.
Caregivers of cancer patients face challenges impacting their physical, psychological and social well-being that need attention in the form of well-designed and tested interventions. We created an eight-session individual stress management intervention for caregivers of allogeneic hematopoietic stem cell transplant (Allo-HSCT) recipients. This intervention, tested by randomized control trial, proved effective in decreasing distress. Herein, we describe the intervention including theoretical framework, development, and elements of fidelity. Implementation challenges along with recommendations for refinement in future studies are discussed with the goal of replication and dissemination.
An increasingly decentralized energy supply structure alongside economic incentives for increasing the level of self-generation and -consumption are encouraging (higher levels of) energy autonomy. Previous work in this area has focused on the technical and economic aspects of energy autonomy at distinct scales, from individual buildings, through neighborhoods to districts. This paper employs a mixed integer linear program (MILP) to assess the effects of aggregation across these scales on the economics of energy autonomy in residential buildings. The model minimizes total energy system costs over the lifetime of the energy system, including micro-combined heat and power (mCHP), photovoltaic (PV), thermal and electrical storage, and boilers, at five distinct scales and for nine demand cases. It is subject to several constraints, among other things the degree of electrical self-sufficiency. The results indicate a shift in the economically optimal level of electrical self-sufficiency with scale, which in Single-Family Houses (SFHs) means from around 30% at the individual building level to almost 100% in districts of 1000 SFH households. Above around 560 households it could be economically advantageous to make a district of residential buildings electrically self-sufficient. In addition, a marginal increase in electrical self-sufficiency is significantly more expensive at lower aggregation scales (i.e. single buildings) compared to the scale of neighborhoods and districts. The level of interaction with the electrical distribution network increases with increasing electrical self-sufficiency before then decreasing at very high (above 70%) levels. Future work should focus on a richer socioeconomic differentiation, considering other sectors and technologies, incorporating demand side options and analyzing the effects on the overarching energy system.
To enhance the performance (i.e., mechanical properties and ionic conductivity) of pore-filling polymer electrolytes, titanium dioxide (TiO2) nanoparticles are added to both a porous membrane and its included viscous electrolyte, poly(ethylene oxide-co-ethylene carbonate) copolymer (P(EO-EC)). A porous membrane with 10wt.% TiO2 shows better performance (e.g., homogeneous distribution, high uptake, and good mechanical properties) than the others studied and is therefore chosen as the matrix to prepare polymer electrolytes. A maximum conductivity of 5.1×10−5 Scm−1 at 25°C is obtained for a polymer electrolyte containing 1.5wt.% TiO2 in a viscous electrolyte, compared with 3.2×10−5 Scm−1 for a polymer electrolyte without TiO2. The glass transition temperature, T g is lowered by the addition of TiO2 (up to 1.5wt.% in a viscous electrolyte) due to interaction between P(EO-EC) and TiO2, which weakens the interaction between oxide groups of the P(EO-EC) and lithium cations. The overall results indicate that the sample prepared with 10wt.% TiO2 for a porous membrane and 1.5wt.% TiO2 for a viscous electrolyte is a promising polymer electrolyte for rechargeable lithium batteries.
New applications of lithium ion batteries in hybrid electric vehicles require high electrochemical performance such as improved power density. High crystalline submicron-size LiNi0.5Mn1.5O4 with high capacity and high rate capability was explored in this work through a low-temperature solid-state reaction route. Samples were characterized by thermal gravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and cell measurements. It is found that LiNi0.5Mn1.5O4 thus obtained has a cubic spinel structure, which can be indexed in a space group of Fd3m with a disordering distribution of Ni. The particle size is about 200nm. Electrochemical tests demonstrated that the as-prepared LiNi0.5Mn1.5O4 possesses high capacity and excellent rate capability. When discharged at a rate as high as of 8C, the as-prepared LiNi0.5Mn1.5O4 powders can still deliver a capacity of 110mAhg−1, which shows to be a potential cathode material for high power batteries.
In making graphite-based electrodes and current collectors, there is significant simplification if a flexible graphite process is used. The lithium intercalation capacity of Grafoil® 1 1 ®GRAFOIL is a registered trademark of Advanced Energy Technology Inc. flexible graphite sheet and its powder was evaluated using electrochemical charge–discharge cycling in half-cell configuration (coin cell with Li anode and graphite cathode). The sheet form was used with and without a copper current collector. Excellent electrical conductivity of the monolithic material with very low interface resistance helps as current collector and electrode. The comparatively low capacity of Grafoil® sheet is thought to be due to diffusion limitation of the structure, especially in the light of the very high capacity of its powder form. The highly irreversible capacity of the powdered material may be due to unfunctionalized graphitic structures or impurities present in the powder. Impedance response for the first intercalation–deintercalation was different than responses taken after several cycles. The presence of a second impedance arc suggests structural modification is taking place in the graphite anode, possibly through formation of a porous structure as a result of graphite expansion.
We designed and evaluated the performance of a tandem technique, consisting of a previously developed versatile aerosol concentration enrichment system (VACES) combined with a compact screen-type diffusion battery that removes ambient ultrafine particles (UFP) from the airflow to enable us to conduct exposures directly on concentrated ambient accumulation mode (0.18–2.5 μm) particles. The performance of the diffusion battery was evaluated first under controlled conditions using NaCl laboratory-generated aerosols. Based on the laboratory tests, the optimum operational conditions of the diffusion battery were selected in terms of the flow rate (i.e., 5 lpm) and number of stages (i.e., 6). The diffusion battery was then deployed to our sampling site in central Los Angeles and connected to the VACES in order to evaluate the performance of the VACES/diffusion battery tandem using concentrated ambient particulate matter (PM2.5). Results of the field tests confirmed the ability of this tandem technique to concentrate effectively the accumulation mode PM with the majority of the ultrafine particles removed from the concentrated aerosol. The 50% cutpoint of the diffusion battery was at around 100 nm, while the removal efficiency exceeded 70–90% for particles smaller than 50 nm. Comparison of the mass concentrations and chemical composition of the accumulation mode PM collected using the tandem technique with those collected using a MOUDI sampler operating in parallel showed excellent overall agreement (within 5–15% variation), corroborating the effectiveness of the VACES/diffusion battery tandem technique for application in exposure studies to concentrated ambient accumulation mode PM.
Battery state of health (SOH) estimation is a crucial challenge for electric vehicles due to the complicated aging mechanism of a battery. In this paper, a new method for battery SOH estimation is proposed using the location interval between two inflection points or the transformation parameter of the differential voltage (DV) curve. And a new algorithm to obtain the DV curve according to the center least squares method is presented. Four LiFePO4 battery cells in different aging states are tested to validate the proposed method. Results show that the linear regression of the location interval between two inflection points versus the battery capacity from one single battery cell is able to evaluate the SOH of other three battery cells within 2% error bound. Transforming the measured DV curve to be congruent with the initial DV curve provided by the manufacturer, battery cell SOH can be estimated according to the transformation parameter with the error being within 2.5%. Furthermore, a battery pack SOH monitoring framework is inferred from the inflection point location and the transformation parameter of the DV curve to realize battery pack SOH estimation.
Objective: Psychiatric disorders, particularly psychosis, depression, personality and behavioral disorders, mental retardation and anxiety disorders, are frequent comorbidities in patients with epilepsy. According to our own recent data, 19.6% of patients with refractory focal epilepsy also have a diagnosis of anxiety disorder. The purpose of the study reported here was to evaluate the efficacy and safety of pregabalin (PGB) in patients with comorbid epilepsy and anxiety disorder. Methods: In an open, uncontrolled study, 45 patients with intractable partial-onset epilepsy were treated with pregabalin at daily doses up to 600mg for 12weeks (including titration) in addition to their existing medication. Two groups of patients were examined: a group with an additional anxiety disorder and one without this comorbidity. In addition to changes in seizure characteristics, changes of psychological parameters were assessed. We used a disorder-specific questionnaire battery in panic disorder and agoraphobia with sub-questionnaires concerning body-related fears (BSQ), cognitions (ACQ), avoidance (MI), the Beck Depression Inventory (BDI), the questionnaire on life satisfaction (FLZ), PESOS, the Symptom Checklist (SCL-90-R), the Social Interaction Anxiety Scale (SIAS), the Social Phobias Scale (SPS) and the State-Trait Anxiety Inventory (STAI). Results: Data are available for 33 patients. Patients with epilepsy and comorbid anxiety disorder (n=12) showed significant improvements in the anxiety and social sensitivity subscales of the SCL-90-R and a positive trend in the phobia subscale. In addition, there was an improvement in the “Trait” subscale of the STAI. Conclusions: Our results indicate favorable effects of PGB on a comorbid anxiety disorder in patients with focal intractable epilepsy. Verification of the data obtained in this study in a large, randomized survey is desirable and necessary. The development and testing of psychotherapeutic methods that are tailored to the comorbidity of epilepsy and anxiety disorder should be discussed. Supported by: Pfizer.
The cycling conditions of silicon nanowires anode are investigated and a set of conditions is proposed in order to improve the cycle life of these electrodes, without any structure or surface optimization. Limitation of lithiation or delithiation to an intermediate value of 900mAhg−1 allows to perform up to 1850 cycles at C/5 rate, which represents a significant increase of the electrode cycle life compared to that observed for standard cycling. This behavior is still attractive at higher current rate. At 1C rate, it is proved that combining the lithiation-limited cycling with an upper cut-off voltage of 0.8V improves the capacity retention by a factor 2. When using these optimized conditions, combined with a simple adding of fluoroethylene carbonate or vinylene carbonate in the electrolyte, a compact solid electrolyte interphase is formed upon cycling and an exceptional capacity retention is observed, reaching respectively 1500 and more than 2000 cycles.
Mechanism-based small-molecule inhibitors targeting a gut microbial enzyme lower circulating levels of the prothrombotic metabolite trimethylamine-N-oxide and suppress diet-induced thrombosis in mice.
Presenting Author details:naya22@neuroimage.snu.ac.kr Department of Psychiatry, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, 110-744 Seoul, Republic of Korea, Tel.: +82 2 2072 1761; fax: +82 2 766 1685. Background: Although a deficit in social cognition is regarded as an early indicator of schizophrenia, few studies have investigated social cognition in ultra high risk (UHR) individuals for psychosis. The present study was designed to investigate the Theory of Mind (ToM) ability in a UHR group compared to that in a healthy control (HC) group. Methods: Our investigation involved subjects at UHR for psychosis (N=33), age and IQ matched HC group (N=36). Three types of theory of mind (ToM) tasks including the False Belief (FB) task, the Strange Stories task and the nonverbal Cartoon task were administrated to assess ToM mind-reading skill. Furthermore, neuropsychological test battery was measured to consider the possible influence of other components of cognitive function such as memory, language, and executive function on ToM ability. Results: Compared to the HC group, the UHR group performed significantly worse for ToM tasks, with the effect size at an intermediate level (0.57–0.74). Furthermore, the UHR group showed impaired performance in the executive and working memory tests, but not verbal memory tests. The deficits for ToM tasks observed in the UHR group were significantly correlated with set-shifting tasks. Conclusions: Deficits in ToM capability may be modest at the prodromal stage of schizophrenia and may be attributed to prefrontal dysfunction. To prevent or delay transition to psychosis, there is a need for specific preventive strategies targeting social functioning for the UHR group.
Lithium-sulfur batteries have high cathode theoretical energy density, but the poor conductivity of sulfur and polysulfide shuttling result in serious polarization and low sulfur utilization. Moreover, the addition of insulating binder in the electrode increases the internal resistance, reducing specific capacity and rate performance. Herein, we develop a composite binder with higher electronic conductivity, superior mechanical property and strong adsorption of polysulfides that imparts it some electrocatalytic activity. The reduced graphene oxide- polyacrylic acid (GOPAA) binder is prepared via a simple solution process. At constant loading fraction of 10wt%, using GOPAA binder induces a 30% enhancement in the cathode capacity, better cycle life and rate capability compared to using PAA binder, reducing both the local charge-transfer resistance and the global electronic resistance before and after cycling. These are attributed to the enhanced binding strength and synergistic effect of reduced graphene oxide and PAA forming well-dispersed conductive bridges to promote rapid electron transfer. Additionally, GOPAA provides active sites for adsorption of lithium polysulfides and electrocatalytic activity, shifting redox peaks in cyclic voltammetry and improving roundtrip efficiency.
Lithium difluoro(oxalato)borate (LiDFOB) with one oxalate moiety bonded to a central boron core was employed as a salt-type additive to enhance the interfacial stabilities of high-voltage Li-rich cathodes and graphite anodes. Our investigation revealed that the LiDFOB additive modified the surface film on the electrodes and effectively restrained degradation of the cycling performance of the electrodes. Investigation of the surface chemistries of the electrodes confirmed that LiDFOB produces a LiF-less surface film on the Li-rich cathode and a LiF-rich surface film on the graphite anode. Moreover, the use of 1% LiDFOB drastically improved the rate capabilities of Li-rich cathodes and graphite anodes. Within 100 cycles at a rate of C/2 at 25 °C, only 45.8% of the initial discharge capacity of a high-voltage Li-rich/graphite full cell was delivered in the baseline electrolyte, while the LiDFOB-containing electrolyte retained 82.7%.