batterydata/paper-abstracts huggingface dataset:
Co3O4, as an attractive lithium ion battery anode material, though benefited from its high theoretical capacity, has long suffered from low electrical transportation and dramatic volume variations. Therefore, to develop a LIB anode material with both good capability and excellent stability, rational design of composite material is becoming an appealing method. Herein, we report a scalable method of fabricating integrated Co3O4/TiO2 composite hollow polyhedrons through a cation-exchange approach in metal-organic framework. In this synthesis, well-defined ZIF-67 particles not only serve as the host to accommodate exchanged titanium cations but also the template to form hollow polyhedron structure. The obtained integrated Co3O4/TiO2 composite hollow polyhedrons exhibit a high reversible capacity of 642mAh/g at a rate of 500mA/g after 200 cycles, accounting for 96.9% of the initial capacity, much higher than that of pure Co3O4, which only maintain a specific capacity of 200mAh/g and a capacity retention of 40%. The optimized integrated Co3O4/TiO2 composite hollow polyhedrons display significant improvements in electrochemical performance, demonstrating great potential as advanced anode material for future lithium ion batteries.
Resumen Introducción Las lesiones cerebrales, según su tipo y localización, pueden afectar tanto la decodificación lectora como la comprensión de textos. Las alteraciones de la decodificación (los cuadros de alexia) se valoran clásicamente con tareas incluidas en las baterías para evaluar pacientes afásicos. Las alteraciones de la comprensión de textos, pese a su mayor frecuencia e importancia ecológica, han recibido menos atención y hay pocos instrumentos destinados a evaluarla. Objetivos Diseñar una batería breve para evaluar alteraciones de la comprensión de textos en pacientes con daño cerebral y probar si resulta apta para diferenciar un grupo de lesionados de su respectivo grupo control. Sujetos y método Se estudiaron 30 pacientes (con traumatismo craneal, lesión en el hemisferio derecho o deterioro cognitivo leve) y 30 controles a los que se les aplicó un test de eficacia lectora (TECLE) y dos pruebas de comprensión de textos especialmente diseñadas. Se comparó el rendimiento de los grupos. Resultados Se encontraron diferencias significativas en el rendimiento de pacientes y controles en las tres pruebas utilizadas. Esto sugiere que las pruebas son útiles para discriminar entre casos y controles. Además, una proporción importante de los pacientes de todas las patologías estudiadas mostró dificultades para comprender textos. Conclusiones Se discute la importancia, clínica y legal, de incluir la dimensión textual en la evaluación de los efectos del daño cerebral y de no reducir la evaluación de la lectura a tareas de decodificación.
Two novel sulfide polymers, poly(2-phenyl-1,3-dithiolane) and poly[1,4-di(1,3-dithiolan-2-yl)benzene], were prepared via facile oxidative-coupling polymerization under ambient conditions, characterized by FT-IR, XRD, TGA and elemental analysis, and were tested as cathode materials in rechargeable lithium battery. The charge–discharge tests showed that the specific capacity of poly[1,4-di(1,3-dithiolan-2-yl)benzene)] was 378mAhg−1 at the third cycle, and retained at 300mAhg−1 after 20 cycles. The specific capacity of poly(2-phenyl-1,3-dithiolane) was 117mAhg−1 at the second cycle, and retained at 100mAhg−1 after 20 cycles. The results indicated that thiolane group could be used as cathode active function group for lithium secondary batteries and the novel electrode reaction is proposed tentatively.
Supercapacitor, as an energy storage device, the capacitance is highly dependent on the properties of material, including its chemical composition and mesoscopic structure. In this study, we report a promising material, nickel-cobalt layered hydroxide, synthesized by simple hydrothermal co-precipitation. The NiCo hydroxides formed flacks first, and then self-assembled to flower-shape nanostructure. Due to its high surface area and the self-assembled structure, the material allows fast diffusion of ions (Ions have direct access to the material surface in the inner surfaces). Hence, the material was used to construct asymmetrical supercapacitor together with nitrogen-doped graphene aerogel. The energy-density of the supercapacitor reached 32 Wh/kg with the power density of 8027 W/kg. The supercapacitor also overcomes the general problem of short cycle-life with supercapacitor made of NiCo layered hydroxides.
We have investigated the oxygen reduction reaction (ORR) in the presence of non-aqueous electrolytes in an attempt to overcome the challenges related to lithium-air batteries, such as low reversibility, poor rate capability, and electrode/solvent stability. We have used glassy carbon as the working electrode in electrolytes composed of lithium bis(trifluoromethanesulfonyl)imide and 1,2-dimethoxyethane or N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR14TFSI, ionic liquid). We have employed the kinetic model to treat the electrochemical impedance spectroscopy data. This approach provides the rate constants for each of the elementary steps and allows indirect investigation of the role played by the ionic liquid in the ORR. The ionic liquid shifts the onset potential of the ORR to more positive values. The presence of the large Pyr14 + cation increases the rate-determining step by approximately three orders of magnitude as compared to the ether-based electrolyte. This ionic liquid is chemically resistant to degradation reactions and increases the rate of the ORR, which makes it a promising candidate for use in lithium-air batteries.
The purpose of this paper is to measure the very small electrochemical noise voltage (about 10nV) generated in batteries. The new method presented here is able to realize these measurements of the noise signal in an industrial environment. The technique we developed is based on a small part of the frequency noise spectrum between 3 and 30Hz. As we will show this seems to offer a good compromise for applications in an industrial environment where a relatively high electrical background noise can be expected to exist. In the proposed measurement setup, we have included the possibility to discriminate between different kinds of noise voltages. This selectivity permits to find indications of different noise generating mechanisms in electrochemical systems, e.g. shot- and burst-noise sources. Measurements confirm the practicability of the proposed measurement setup.
Na2FeP2O7, which is considered as a promising cathode for sodium ion batteries (SIBs) on account of its economical efficiency and outstanding thermal stability, has been widely studied for the purpose of enhancing its electronic conductivity and interface ion transportation. In this paper, a double-carbon synergistically modified strategy was firstly introduced to facilitate the electrochemical performance of Na2FeP2O7. Na2FeP2O7 particles are enwrapped in situ by a carbon layer and further anchored in reduced graphene oxide (RGO) framework through a facile urea-nitrate combustion method. Consequently, the excellent rate performance and durable cycle stability of this compound are identified, which exhibits a reversible sodium storage capacity of 65 mAh g−1 at a current density of 10 C and no obvious decay in capacity after circling for 300 cycles at 1 C. What's more, no drastic degradation in capacity is observed when the cycling current density is brought back to high rates after cycling for more than 360 cycles at various rates.
A novel way for the synthesis of core/shell structures composed of tin oxide nanoparticles confined in mesoporous hollow carbon spheres (SnO2@MHCS) is newly reported. The materials which have a uniform size distribution, good structural stability and large surface area show superior cycling performance and are suitable for high-power anodes. Core/shell structured SnO2@MHCS takes advantage of the virtues of SnO2 and porous carbon in lithium-ion battery. This structure provides a rapid lithium transport pathway and boasts a highly reversible capacity. When the SnO2/C ratio is 78.6/21.4 (w/w), the surface area of SnO2@MHCS is 183 m2 g−1 and specific capacity value is 450 mAh g−1 at 1/5 C after 50 cycles. The SnO2@MHCS materials have large potential in next-generation lithium-ion batteries.
Upon the emergence of electric vehicles, accurate and non-destructive monitoring of battery electrode materials during operation is highly desirable. Structural degradation of widely adopted intercalation-based materials constitutes the origin of their capacity fading and safety deterioration. Here, we introduce entropymetry to monitor the structural changes of LiCoO2 (LCO) and its nickel (Ni)-doped derivatives at different states of charge (SOC). While simple lithium (Li) extraction on charging gives a monotonic decline of entropy change (ΔS) based on progressive vacancy occupation over Li sites, the presence of a monoclinic intermediate phase inverses the slope of the ΔS profile to reflect its limited atomic configurations with high ordering. Furthermore, Ni-doping lessens the ordering of the monoclinic phase, decreasing the height amplitude of ΔS profile in the monoclinic regime. The increased disorder by Ni-doping enhances the stability of the lattice framework, extending the cycle life with high voltage cut-off (4.6 V vs. Li/Li+). The present study highlights entropymetry as a unique, non-destructive tool in monitoring the structural ordering and relevant degradation of electrode materials in lithium-ion batteries.
The influence of the surface film formed on the graphite surface in ethylene carbonate (EC) on the lithium intercalation reaction into graphite in other electrolyte solutions including propylene carbonate (PC) was investigated. A graphite sample could be charged and discharged in PC+DME, while no lithium intercalation occurred in either PC+DMC or in PC+DEC. However, the lithiated graphite (LiC6) obtained from a charge in EC with 1moldm3 LiPF6 exhibited a reversible intercalation reaction with a large discharge capacity (370mAhg−1) and a good cycle performance even in PC+DMC. This result suggests that nature of the surface film formed in EC is a dominant factor in the reactivity of graphite with lithium ions in PC+DM, In PC+DME, the reversible capacity was smaller in both cases of the as-manufactured graphite and the LiC6 obtained in EC. An XRD analysis indicated that the reduction in the crystalline size along the c-axis during the initial lithium intercalation is responsible for the smaller capacity.
To test the effect of motor imagery as compared to voluntary muscle contraction on the excitability of the anterior horn cells, we studied F-wave persistence and amplitude, monitoring the force by a transducer. F-waves were recorded from the first dorsal interosseus muscle at rest and under a battery of motor tasks which comprised mental imagery and mild to moderate abduction of the index finger in 10 increments up to 30% of the maximal force. During each step lasting for 20s, 20 stimuli were applied to the ulnar nerve at the wrist at the rate of one per second. In 12 healthy subjects, F-wave persistence (mean±SD) significantly (p<0.05) increased from 32.5±11.9% at rest to 58.3±15.2% during motor imagery and to 87–91% during voluntary contraction. Similarly, F-wave amplitude significantly (p<0.05) increased from 41.3±77.1μV at rest to 91.2±142.7μV during motor imagery and to 183–274μV during voluntary contraction. In contrast, F-wave latency changed little regardless of motor tasks. Motor imagery, though to a lesser degree than muscle contraction, effectively enhances the excitability of the anterior horn cells, thereby increasing F-wave persistence and amplitude above the baseline.
Electrode materials composed of micrometer- and sub-micrometer-sized spherical particles are of interest for lithium ion batteries (LIBs) because spheres can be packed with higher efficiency than randomly shaped particles and achieve higher volumetric energy densities. Here we describe the synthesis of lithium iron phosphate (LFP) phases as cathode materials with spherical morphologies. Spherical Li3Fe2(PO4)3 particles and LiFePO4 spheres embedded in a carbon matrix are prepared through phase separation of precursor components in confinement. Precursors containing Li, Fe, and P sources, pre-polymerized phenol–formaldehyde (carbon source), and amphiphilic surfactant (F127) are confined in 3-dimensional (colloidal crystal template) or 2-dimensional (thin film) spaces, and form spherical LFP particles upon heat treatment. Spherical Li3Fe2(PO4)3 particles are fabricated by calcining LiFePO4/C composites in air at different temperatures. LiFePO4 spheres embedded in a carbon matrix are prepared by spin-coating the LFP/carbon precursor onto quartz substrates and then applying a series of heat treatments. The spherical Li3Fe2(PO4)3 cathode materials exhibit a capacity of 100 mA h g−1 (83% of theoretical) at 2.5 C rate. LiFePO4 spheres embedded in a carbon matrix have specific capacities of 130, 100, 83, and 50 mA h g−1 at C/2, 2 C, 4 C, and 16 C rates, respectively (PF_600_2), revealing excellent high-rate performance.
A novel process via sintering of a precursor from the solution of metal acetates by spray-drying technology was used to synthesize Co-substituted LiCo1/6Mn11/6O4 material for lithium ion batteries. The as-prepared particles were identified as single-phase spinel structure without any impurities in the XRD pattern. The SEM image showed that the particles had good cubic shapes and uniform size distribution with sizes of about 100–200nm. An ex situ XRD technique was used to characterize the first charge process of the LiCo1/6Mn11/6O4 electrode. The result suggested that the material configuration maintained invariability. The electrochemical properties of the synthesized cathode material were investigated using Li-ion model cells at room and elevated temperature, respectively. In the charge/discharge potential of 3.5–4.4V at 1/10C rate, the LiCo1/6Mn11/6O4 electrode delivered high initial capacities of 123 and 127mAhg−1 at 25 and 55°C, respectively. Electrochemical cycling tests revealed that the capacity fading occurred mainly in the high-voltage region of 4.08–4.40V, and the fading rate was 0.107% and 0.302% per cycle at 25 and 55°C, respectively. The excellent cycling stability and low material cost make it an attractive cathode for high-temperature lithium ion batteries.
Lay people have a large appetite for information about scientific and technological issues that affect them, such as self-driving automobiles, gene manipulation, and climate change. However, this information must be clear and accurate if they are to use it to make informed political decisions. In 1994, the Nobel prize–winning physicist Philip W. Anderson used a newspaper essay to convey his concerns about the fidelity of the communication channels that connect the public to the creators of technical knowledge. He also suggested strategies to improve the quality of that communication. We analyze that essay and other writings by Anderson to identify the origins of his concerns and to place them in the larger context of his scientific philosophy.
Poly (3, 4-ethyleendioxythiophene) (PEDOT) coated titanium dioxide (TiO2) nanoparticles were prepared through a soft chemistry approach-assisted in situ synthesis route. The as synthesized PEDOT/TiO2 nanocomposites (NCs) are characterized by XRD, Raman, BET, XPS, SEM, TEM and EDX analysis/elemental mapping. The formation mechanism of PEDOT/TiO2 NCs is also illustrated. The uniformly TiO2 nanoparticles dispersed in PEDOT matrix improving the electrochemical performance of the ternary PEDOT/TiO2/sulfur composite, which exhibits higher reversible capacity and better rate capability compared with the PEDOT/S and TiO2/S composites. The reversible capacity of PEDOT/TiO2 NCs can be up to 1110mAhg−1 and was retained 532.1mAhg−1 after 500 charge-discharge cycles at the rate of 1C, which confirms the good cycling behavior. The superior electrochemical performance of the PEDOT/TiO2 NCs could be attributed to the uniform conducting polymer layer and improving the electrical conductivity of TiO2, the lower charge-transfer resistance and larger lithium ion diffusion coefficient.
Background Obliterative bronchiolitis (OB) remains one of the leading causes of death in lung transplant recipients after 2 years, and acute rejection (AR) of lung allograft is a major risk factor for OB. Treatment of AR may reduce the incidence of OB, although diagnosis of AR often requires bronchoscopic lung biopsy. In this study, we evaluated the utility of exhaled-breath biomarkers for the non-invasive diagnosis of AR. Methods We obtained breath samples from 44 consecutive lung transplant recipients who attended ambulatory follow-up visits for the Johns Hopkins Lung Transplant Program. Bronchoscopy within 7 days of their breath samples showed histopathology in 21of these patients, and we included them in our analysis. We measured hydrocarbon markers of pro-oxidant events (ethane and 1-pentane), isoprene, acetone, and sulfur-containing compounds (hydrogen sulfide and carbonyl sulfide) in exhaled breath and compared their levels to the lung histopathology, graded as stable (non-rejection) or AR. None of the study subjects were diagnosed with OB or infection at the time of the clinical bronchoscopy. Results We found no significant difference in exhaled levels of hydrocarbons, acetone, or hydrogen sulfide between the stable and AR groups. However, we did find significant increase in exhaled carbonyl sulfide (COS) levels in AR subjects compared with stable subjects. We also observed a trend in 7 of 8 patients who had serial sets of breath and histopathology data that supported a role for COS as a breath biomarker of AR. Conclusions This study demonstrated elevations in exhaled COS levels in subjects with AR compared with stable subjects, suggesting a diagnostic role for this non-invasive biomarker. Further exploration of breath analysis in lung transplant recipients is warranted to complement fiberoptic bronchoscopy and obviate the need for this procedure in some patients.
Cobalt nanosheet arrays supported silicon film is prepared and used as anode materials for lithium ion batteries. The film is fabricated using chemical bath deposition, hydrogen reduction and radio-frequency magnetron sputtering techniques. The microstructure and morphology are characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). In this composite film, the silicon layer is supported by interconnected aligned cobalt nanosheet arrays that act as the three-dimensional current collector and buffering network. The electrochemical performance as anode materials for lithium ion batteries is investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge tests. The results show that the film prepared by sputtering for 1500s exhibits high capacity, good rate capability and stable cycle ability. It is believed that the cobalt nanosheet arrays play important roles in the electrochemical performance of the silicon layer.
A cohort study was designed to evaluate the efficiency of gene transfer and whether biological activity from the expressed therapeutic gene resulted after administration of a recombinant adenovirus containing the human wild-type p53 (p53wt) gene (rAd-p53 SCH 58500). The cohort study was conducted in five trial subjects with recurrent ovarian cancer. Each trial subject received multiple cycles of rAd-p53 SCH 58500, each cycle comprised of doses of 7.5 × 1013 particles on each of five consecutive days. Subjects were treated with rAd-p53 SCH 58500 alone during Cycle 1 and in combination with gemcitabine during the subsequent cycles. Both tumor biopsies and peritoneal aspirates were collected and evaluated for gene transfer and evidence of the biological activities of the expressed p53wt gene. Using quantitative PCR and RT-PCR, and in situ PCR, gene transfer and expression were documented in tumor biopsies (four of five patients) collected from Cycle 1. Furthermore, upregulation of p21/WAF1, bax and mdm-2, and downregulation of survivin were observed in these same tumor biopsy samples, suggesting that intraperitoneal administration of rAd-p53 SCH 58500 leads to detectable p53 biological activity in target tumor tissue. In addition, gene transfer and its expression were observed in cells obtained from peritoneal aspirates. These fluids were mainly comprised of polymorphonuclear neutrophils, indicating that successful gene transfer can be achieved by multiple cycle intraperitoneal administration of recombinant adenovirus.
We examined (a) what rapid automatized naming (RAN) components (articulation time and/or pause time) predict reading and mathematics ability and (b) what processing skills involved in RAN (speed of processing, response inhibition, working memory, and/or phonological awareness) may explain its relationship with reading and mathematics. A sample of 72 children were followed from the beginning of kindergarten until the end of Grade 1 and were assessed on measures of RAN, general cognitive ability, speed of processing, attention, working memory, phonological awareness, reading, and mathematics. The results indicated that pause time was the critical component in both the RAN–reading and RAN–mathematics relationships and that it shared most of its predictive variance in reading and mathematics with speed of processing and working memory. Our findings further suggested that, unlike the relationship between RAN and reading fluency in Grade 1, there is nothing in the RAN task that is uniquely related to math.
Clinically significant dysregulation of the insulin-like growth factor (IGF) family proteins occurs in HIV-infected individuals, but the details including whether the deficiencies in IGFs contribute to CNS dysfunction are unknown.
Marine animals face increased pressure through expanded shipping and recreational activities. Effective conservation and management of large species like marine mammals or sea turtles depend on knowledge of movement and habitat use. Previous studies have used data collected from either satellite or acoustic telemetry but rarely both. In this study, data from satellite and acoustic technologies were used to: determine the efficacy of satellite and acoustic telemetry to define dugong movement patterns; compare the benefits and limitations of each approach; examine the costs of each approach in relation to the amount and type of data provided; and relate telemetry data to the boundaries of a Go Slow area designed to protect dugongs and turtles from vessel strike within an urbanised coastal embayment (Moreton Bay, Queensland, Australia). Twenty-one dugongs were captured in seagrass habitats on the Eastern Banks of Moreton Bay in July–September 2012 and July 2013 and fitted with GPS and acoustic transmitters. Both satellite and acoustic telemetry produced reliable presence and movement data for individual dugongs. When the dugongs were within the range of the acoustic array, there was relatively good correspondence between the overall space use measures derived from GPS and acoustic transmitters, demonstrating that acoustic tracking is a potentially valuable and cost-effective tool for monitoring local dugong habitat use in environments equipped with acoustic receiver arrays. Acoustic technology may be particularly useful for species that establish home ranges with stable residency especially near large urban or port environs. However, the relative merits of the two technologies depend on the research question in the context of the species of interest, the location of the study and whether the study site has an established acoustic array.