batterydata/paper-abstracts huggingface dataset:
LiNi0.8Co0.2O2 cathode powders for lithium-ion batteries were prepared by a modified sol–gel method with citric acid as chelating agent and a small amount of hydroxypropyl cellulose as dispersant agent. The structure and morphology of LiNi0.8Co0.2O2 powders calcined at various temperatures for 4 h in air were characterized by means of powder X-ray diffraction analyzer, scanning electron microscope, thermogravimetric analyzer and differential thermal analyzer, and Brunauer–Emmett–Teller specific surface area analyzer. The results show that LiNi0.8Co0.2O2 powders calcined at 800 °C exhibit the best layered structure ordering and appear to have monodispersed particulates surface. In addition, the electrochemical properties of LiNi0.8Co0.2O2 powders as cathode material were investigated by the charge–discharge and cyclic voltammetry studies in a three-electrode test cell. The initial charge–discharge studies indicate that LiNi0.8Co0.2O2 cathode material obtained from the powders calcined at 800 °C shows the largest charge capacity of 231 mAh g−1 and the largest discharge capacity of 191 mAh g−1. And, the cyclic voltammetry studies indicate that Li+ insertion and extraction in LiNi0.8Co0.2O2 powders is reversible except for the first cycle.
Background and purpose Correlated with better follow-up of gliomas, cognitive disorders are increasingly studied. The aim of this study was to describe the cognitive disorders presented by these patients at baseline, before any treatment, and to evaluate the relations between cognitive disorders and return to work. Methods A detailed neuropsychological evaluation was administrated to 15 newly diagnosed patients with a grade II or III glial tumor before any treatment. Patients also completed the quality of life and depression scales. Results All patients in our study presented with at least one failed cognitive domain during the detailed examination, while the scores on the MMSE scale were within the norm. The most deteriorated functions were divided attention and episodic verbal and nonverbal memory. Moreover, a significant link was found between the number of failed cognitive functions and quality of life. Conclusion Cognitive disorders are frequent with glial tumors and impact patients’ quality of life. Simple tests of global cognitive status are not sufficient to detect cognitive difficulties in these patients. Consequently, detailed and adapted neuropsychological assessment is necessary, especially to detect deteriorated problems with memory, divided attention, or processing speed in this population.
The severe capacity fading and poor rate performance under high voltage of LiNi0.5Co0.2Mn0.3O2 are the vital barriers for their large scale application. In order to solve above issues, zirconium doped LiNi0.5Co0.2Mn0.3O2 materials were prepared by solid state method. The effects of the zirconium content on the structure and electrochemical properties of Li(Ni0.5Co0.2Mn0.3)1-x Zr x O2 were extensively studied. Though the zirconium doped samples delivered lower initial capacities, the cycling stability are dramatically enhanced. Notably, Li(Ni0.5Co0.2Mn0.3)0.99Zr0.01O2 showed a capacity retention of 83.78% at 1C after 100 repeated cycle in a high voltage of 4.6V, while that of bare sample remains only 69.35%. Moreover, the rate capability of Li(Ni0.5Co0.2Mn0.3)0.99Zr0.01O2 is also greatly reinforced especially at high current density. The improved electrochemical performances could be ascribed to the less cation mixing degree, better lithium transportation kinetic and lower impedance, which were confirmed by Rietveld refinement, X-ray photoelectron spectroscopy and electron impedance spectroscopy.
Publisher Summary This chapter provides an overview of the automobile with emphasis on the basic operation of the engine, thus providing the background to how electronic controls have been and are applied. The basic automobile components and systems are reviewed as they pertained to the post-World War II, pre-emissions control era. This review provides a framework within which the present day automobile with its extensive use of electronics can be understood. In this sense, the motivation for applying electronics to solve regulatory problems imposed on the industry can be readily seen. The influence of the shock absorber damping on wheel motion is explained. This chapter briefly reviews the major systems of the automobile and discusses basic engine operation, and also indicates where electronic technology could be applied to improve performance or reduce cost.
Lithium hexafluorophosphate (LiPF6) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) are used as Li salts in butylmethylpyrrolidinium–bis(trifluoromethanesulfonyl)imide (BMP–TFSI) ionic liquid (IL) electrolyte for Li/LiFePO4 cells. This kind of IL electrolyte shows high thermal stability (>400°C) and non-flammability, and is thus ideal for high-safety applications. At 25°C, a maximum capacity of 113mAhg−1 (at 0.1 C) is found for LiFePO4 in the IL with 0.5M LiTFSI. An excessive LiTFSI concentration leads to a capacity decrease due to reduced electrolyte ionic conductivity. At 50°C, the measured capacity and rate capability are significantly improved compared to those at 25°C. With 1M LiTFSI-doped IL electrolyte (the optimum concentration at 50°C), a capacity of 140mAhg−1 is found at 0.1 C and 45% of the capacity can be retained when the rate increases to 5 C, values which are comparable to those found in a traditional organic electrolyte. In the IL electrolyte, the LiFePO4 electrode shows better cyclic stability at 50°C than it does at 25°C; this trend is opposite to that found in the organic electrolyte. At 50°C, there is negligible capacity loss of LiFePO4 after 100 charge–discharge cycles in 1M LiTFSI-doped BMP–TFSI IL electrolyte.
Thermodynamics is a core part of science. Nearly all scientists should have a basic knowledge of thermodynamics. Thermodynamics is a science of development, and is a viewpoint of scientific development in natural sciences. Achievement of thermodynamics has influence not only on natural sciences, but also on social sciences and philosophy. Fundamental concepts and definitions are very important for any discipline of science, so what is classical thermodynamics and what is modern thermodynamics have become the key points of puzzledom in thermodynamics. In this paper, after clarification of fundamental concept in thermodynamics, a complete basic modern classification of thermodynamics is naturally obtained. It is suggested that extended Carnot theorem and dissipation decrease theorem, together with the laws of thermodynamics, are the most fundamental theorems in thermodynamics discipline. Nondissipative thermodynamics is a new field besides equilibrium thermodynamics belonging to the equal part of the second law of thermodynamics.
When the early trials of Ginkgo biloba extract EGb 761® were conducted, different terms were used to denote ageing-associated neurocognitive disorders. With the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), a taxonomy covering dementia and pre-dementia stages of such disorders became available. DSM-5 diagnostic criteria for neurocognitive disorders (NCDs) were applied to patients with any type of ageing-associated cognitive impairment, including dementia, enrolled in randomized controlled clinical trials of EGb 761®, taking into account the reported inclusion and exclusion criteria and patient characteristics at baseline. For 23 of 31 trials (74 %), the inclusion diagnoses could be classified as NCD in accordance with DSM-5. Thirteen trials enrolled patients with major NCD, four trials enrolled patients with mild NCD and six trials enrolled patients with NCD, who could not be classified unambiguously as having mild or major NCD. Although various terms were formerly used for neurocognitive disorders, the patients enrolled in the majority of clinical trials with EGb 761® could be classified retrospectively using modern DSM-5 diagnostic criteria.
A simple synthetic method is developed for the synthesis of CoS2/N, S-codoped graphene. The result shows the existence of a strong electronic coupling between CoS2 and N, S-codoped graphene. The pyrrolic and pyridinic type nitrogen and S in the form of C-S-C in N, S-codoped graphene are found to be the anchoring sites of the CoS2 nanoparticles. As a bifunctional catalyst, the CoS2/N, S-codoped graphene exhibits an oxygen reduction onset potential of 0.963 V vs. RHE and delivers an oxygen evolution overpotential of 393 mV at the current density of 10 mA cm−2. Its oxygen reduction and evolution catalytic activities are comparable to those of the Pt/C and the state-of-art RuO2/C, respectively. Most impressively, the CoS2/N, S-codoped graphene exhibits a potential gap of 771 mV. This value is lower than those of most bifuntional catalysts reported, clearly indicating its potential use as the bifunctional catalyst to replace the noble-metal based catalysts for practical applications. Additionally, our results also suggest a great importance to prepare a single pure phase CoS2 in improving the catalytic bifunctionality of the CoS2/N, S-codoped graphene. The primary Zn-air battery with CoS2/N, S-codoped graphene shows a higher discharge peak power density than that with Pt/C.
Published data from various sources are used to perform economic and environmental comparisons of four types of vehicles: conventional, hybrid, electric and hydrogen fuel cell. The production and utilization stages of the vehicles are taken into consideration. The comparison is based on a mathematical procedure, which includes normalization of economic indicators (prices of vehicles and fuels during the vehicle life and driving range) and environmental indicators (greenhouse gas and air pollution emissions), and evaluation of an optimal relationship between the types of vehicles in the fleet. According to the comparison, hybrid and electric cars exhibit advantages over the other types. The economic efficiency and environmental impact of electric car use depends substantially on the source of the electricity. If the electricity comes from renewable energy sources, the electric car is advantageous compared to the hybrid. If electricity comes from fossil fuels, the electric car remains competitive only if the electricity is generated on board. It is shown that, if electricity is generated with an efficiency of about 50–60% by a gas turbine engine connected to a high-capacity battery and an electric motor, the electric car becomes advantageous. Implementation of fuel cells stacks and ion conductive membranes into gas turbine cycles permits electricity generation to increase to the above-mentioned level and air pollution emissions to decrease. It is concluded that the electric car with on-board electricity generation represents a significant and flexible advance in the development of efficient and ecologically benign vehicles.
Intermetallic compounds with nominal formula CaNi5−x Cu x (x =0, 1, 2.5) have been prepared in order to investigate their hydrogenation properties. The samples were obtained by arc-melting and were deuterated in a Sieverts reactor. For x =0 and 1, we have found that the fast kinetics and the different shape of the curve (non sigmoidal) in the second absorption process indicate an improvement of the hydrogen absorption due to the activation of the alloys. The deuterium desorption spectra are similar for x =0 and 1 whereas for x =2.5 the desorption ranges a broader temperature interval (∼100–350°C) indicating a certain degree of chemical inhomogeneity or amorphization intrinsic to the parent sample or induced by the deuterium absorption. The formed deuterides were passivated in the presence of air in order to carry out a neutron diffraction study, allowing us to determine the deuterium positions in the samples. While in CaNi4CuD y the deuterium is randomly distributed over seven different positions, in CaNi5D y the deuterium only occupies five of them. This wider distribution in CaNi4CuD y can explain its higher stability, and therefore, its higher desorption temperature for deuterium.
Research has repeatedly shown that early adversities are a risk factor for psychological distress in adulthood. However, limited research has examined the association between early adversities and intraindividual changes in psychological distress among middle-aged adults. This study developed a self-report scale to retrospectively measure the level of adversity experienced in childhood (Early Environment Scale: EES) and investigated the association between the EES score and the change in psychological distress in middle-aged adults. Study 1 examined the reliability and validity of the nine-item EES using a sample of 337 Japanese adults (162 women; Meanage = 42.96, SDage = 10.55). In Study 2, a three-wave six-month longitudinal survey was conducted with a sample of 2000 Japanese adults (1000 women; Meanage = 40.94; SDage = 5.35). Psychological distress at all three waves was measured with the Kessler Psychological Distress Scale (K-6). The results from a latent growth analysis showed significant positive associations between early adversities and the intercept and slope factors of psychological distress. Specifically, individuals who reported more early adversity showed higher initial levels of psychological distress and a stronger increase in psychological distress among Japanese middle-aged adults. Early adversities might influence the development of dispositional sensitivity for psychological distress in adulthood.
Polytetrafluoroethylene (PTFE)-bonded gas-diffusion electrodes (GDEs), modified with polyaniline as an electron and proton conductor in the catalyst layer, are prepared and evaluated for use in proton-exchange membrane fuel cells (PEMFCs). Polyaniline is coated on the GDE by electropolymerization of aniline and trifluoromethane sulfonic acid as the proton-conductive monomer. The electrodes are characterized by cyclic voltammetry, current–potential measurements, electrochemical impedance spectroscopy, and chronoamperometry. The polyaniline is found to be homogenously dispersed in the catalyst layer, making it a good candidate proton and electron conductor. Use of polyaniline instead of Nafion in the catalyst layer, increases the utility of the electrocatalyst by 18%. The results are consistent with the presence of polyaniline as a conductive polymer in the reaction layer reducing the polarization resistance of the electrode in comparison with that of a corresponding electrode containing Nafion. Thus, the present results indicate that PEMFCs using polyaniline-containing electrocatalysts should give superior performance to those using catalysts containing traditional ionomers.
Although functionalized carbon-based materials have been widely used as the supercapacitor electrodes, the optimum contents of the functional groups, the charge storage mechanisms, and the effects of electrolytes and operating temperature have not yet been clearly investigated. In this work, carboxylate-modified hollow carbon nanospheres (c-HCN) with different functional group contents synthesized by an oxidation process of carbon nanospheres with nitric acid were coated on flexible carbon fibre paper and used as the supercapacitor electrodes. An as-fabricated supercapacitor of the c-HCN with a finely tuned 6.2 atomic % of oxygen of the oxygen-containing groups in an ionic liquid electrolyte exhibits a specific capacitance of 390Fg−1, a specific energy of 115Whkg−1, and a maximum specific power of 13548Wkg−1 at 70°C. The charge storage mechanism investigated is based on the chemical adsorption of the ionic liquid electrolyte on the c-HCN electrode. This process is highly reversible leading to high capacity retention. The supercapacitor in this work may be practically used in many high energy and power applications.
Photovoltaic-powered membrane filtration (PV-membrane) systems are of interest for the provision of clean drinking water in small communities, especially in remote areas. In order to deliver clean water at the lowest cost over the lifetime of the system, a reliable and robust design is paramount. This paper provides a comprehensive review of the operating range and reliability of all components of a small-scale PV-membrane system for brackish water desalination. The failure and degradation modes, as well as lifetime and robustness issues associated with field operation are discussed and best-practice recommendations made. The outcomes of this paper suggest that a small-scale (power rating <1.5 kW) PV-membrane system – based on a helical rotor pump driven by a direct-current brushless motor and powered by silicon photovoltaic modules – may achieve a lifetime of 20 years, while operating with a specific energy consumption of 1.5–3 kWh/m3. Possible methods for mitigating the effects of membrane fouling and damage are also discussed. To maximize membrane lifetime, such systems ought to be operated with a recovery of less than 30% and limit the rate of change of pressure (induced by fluctuations in solar irradiance) to less than 0.7 bar/s. The analysis is useful for identifying the optimal combination of components, system operation and possible reliability improvements. The investigation into component and system failures allows the weakest links to be avoided and enable the optimization of future systems. This review is intended as valuable reference for engineers engaged in the field of renewable-energy-powered membrane filtration technologies.
A lithium phosphorus oxynitride (LiPON) glass-electrolyte thin film is coated on a lithium cobalt oxide (LiCoO2) composite cathode by means of a radio frequency (RF) magnetron sputtering method. The effect of the LiPON coating layer on the electrochemical performance and thermal stability of the LiCoO2 cathode is investigated. The thermal stability of the delithiated LiCoO2 cathode in the presence of liquid electrolyte is examined by differential scanning calorimetry (DSC). It is found that the LiPON coating, improves the rate capability and the thermal stability of the charged LiCoO2 cathode. The LiPON film appears to suppress impedance growth during cycling and inhibits side-reactions between delithiated LiCoO2 and the electrolyte.
We demonstrate the unsuitability of LiV3O8 as an electrode material for aqueous rechargeable lithium batteries on simple but solid grounds: the compound is unstable under typical battery operation conditions, where it slowly dissolves as reflected in the yellow color acquired by the electrolyte. This can be the origin of the poor performance of the aqueous batteries based on this compound.
A simplified 5-RC transmission line equivalent circuit was introduced. Manganese dioxide cathodes from three commercial primary alkaline cells were investigated by means of ac impedance technique. Cathode Ohmic resistance, Faraday resistance for the reduction of MnO2, proton diffusion rate inside the lattice of EMD and electrochemical accessible surface area were obtained by numerical fitting of impedance data using the simplified transmission line model. The kinetics for cathode surface accessibility was also studied.
Application of advanced anode and cathode materials in commercial lithium-ion batteries is attracting attention due to their high capacity. Silicon (Si)/graphite anodes and nickel (Ni)-rich lithium nickel manganese cobalt oxide with layered structures have been paired in commercial 18650 high energy density cells (∼270 Wh/kg). It is crucial to investigate the cell performance and the aging behavior of this commercial cell. In this study, we present commercial cell degradation mechanisms by comparing fresh and aged electrodes, including changes of crystal structure, morphology, elemental composition, and electrochemical properties. The quantitative analysis was done based on dV/dQ incremental capacity analysis of 18650 cells. To determine the amount of cyclable lithium ions (Li+) and active material loss, the lithiation and delithiation capacity were compared for fresh and aged electrodes in half coin cells. Results showed that even with 5% (by mass) of Si added in the anode, cracks occurred across the anode leading to contact loss and thickening of the solid electrolyte interphase (SEI) layer. Additionally, the average fluorine (F) ratio of the aged anodes was higher compared to that of the fresh anodes. More severely, the F content on the Si aggregations on aged anodes increased to as high as 5 times that of the fresh anode, indicating SEI growth, especially on Si particles. Solid 7Li nuclear magnetic resonance results showed no detectable Li metal deposition on the aged anode. On the cathode side, cracks on the primary particle interfaces contributed to cathode material loss, contact loss, and impedance rise. Therefore, Li+ loss into the thickened SEI layer, particle cracking, and impedance rise are the main reasons behind cell degradation.
While there is growing evidence that some dyslexic children suffer from a deficit in simultaneously processing multiple visually displayed elements, the precise nature of the deficit remains largely unclear. The aim of the present study is to investigate possible cognitive impairments at the source of this deficit in dyslexic children. The visual processing of simultaneously presented letters was thus thoroughly assessed in two dyslexic children by means of a task that requires the report of briefly presented multi-letters arrays. A computational model of the attentional involvement in multi-object recognition (Bundesen, 1990, 1998) served as framework for analysing the data. By combining psychophysical measurements with computational modelling, we demonstrated that the visual processing deficit of simultaneously displayed letters, observed in the two dyslexic individuals reported in the current study, stems from at least two distinct cognitive sources: a reduction of the rate of—letter—information uptake, and a limitation of the maximal number of elements extracted from a brief visual display and stored in visual short-term memory. Possible relations between these impairments and learning to read proficiently are discussed.
The variable number of tandem repeat polymorphism in the 3′-untranslated region of the dopamine transporter gene (DAT) may influence the variability of the therapeutic response to methylphenidate (MPH) in Attention Deficit/Hyperactivity Disorder (ADHD). For this reason we evaluated the neuropsychological functioning after a prolonged period of MPH treatment and after a specific time from MPH suspension. Relationship between DAT VNTR genotypes and neurocognitive response to MPH was analyzed in a sample of 108 drug-naive ADHD patients. The performance of children with ADHD on measures of working memory, inhibition and planning was assessed at 4, 8 and 24 weeks and at 8 weeks after MPH withdrawal. Patients with 9/9 genotype evidenced an improvement in response inhibition and working memory only at 4 weeks of treatment, in planning at 24 weeks of therapy and after 8 weeks of MPH suspension. Patients with 9/10 showed an improvement in response inhibition at 4, 8 and 24 weeks of treatment, in planning at 24 weeks and after 8 weeks of MPH suspension. Patients with 10/10 evidenced an improvement in response inhibition and working memory at 4, 8 and 24 weeks of treatment and in planning at 4, 8 and 24 weeks of treatment and after 8 weeks of suspension. These results indicate that the 9/9 ADHD genotype has a different response at 24 weeks treatment with MPH. 10/10 DAT allele seems to be associated with an increased expression level of the dopamine transporter and seems to mediate the MPH treatment response in ADHD patients.