batterydata/paper-abstracts huggingface dataset:
Platinum (Pt) -free counter electrodes (CEs) for dye sensitized solar cells (DSSCs) were developed using freestanding flexible single wall carbon nanotube (SWNT) films called bucky papers (BPs). BP was irradiated with microwave plasma, created using a mixture of Ar (1%) and H2 (99%) gases, for 2 h. Raman scattering measurements revealed that no significant defects were created in the SWNTs as a result of the treatment. Plasma-treated BP (P-BP) developed vertically oriented, micron sized, pillar-like structures on its surface, while its base was still a dense random mesh of SWNTs. This unique flexible film had a larger accessible surface area and better catalytic properties. The plasma treatment improved the efficiency of BP-based DSSCs from 2.44% to 4.02%, which is comparable to Pt thin film (4.08%). The P-BP based solar cell operated with an open circuit voltage of 0.73 V and a fill factor of 0.70. It also had much higher efficiencies than films of randomly oriented plasma treated SWNTs. Using electrochemical impedance spectroscopy, the charge transfer resistances of P-BP and Pt were found to be 1.46 and 1.73 Ω cm2, respectively.
Polyanion based silicate materials, MgMSiO4 (M = Fe, Mn, Co), previously reported to be promising cathode materials for Mg-ion batteries, have been re-examined. Both the sol-gel and molten salt methods are employed to synthesize MgMSiO4 composites. Mo6S8 is synthesized by a molten salt method combined with Cu leaching and investigated in the equivalent electrochemical system as a bench mark. Electrochemical measurements for Mo6S8 performed using the 2nd generation electrolyte show similar results to those reported in literature. Electrochemical performance of the silicate materials on the other hand, do not show the promising results previously reported. A thorough study of these published results are presented here, and compared to the current experimental data on the same material system. It appears that there are certain inconsistencies in the published results which cannot be explained. To further corroborate the present experimental results, atomic-scale calculations from first principles are performed, demonstrating that diffusion barriers are very high for Mg diffusion in MgMSiO4. In conclusion, MgMSiO4 (M = Fe, Mn, Co) olivine materials do not seem to be such good candidates for cathode materials in Mg-ion batteries as previously reported.
As vitamin D deficiency is considered to be more common in regions with little solar ultraviolet (UV) light in winter, the aim of this study was to analyze predictors of vitamin D status by season within a large sample of male smokers from Finland, a country where there is negligible solar UV light in winter.
This paper presents a dynamic data-driven method of pattern classification for identification of the state-of-charge (SOC) parameter in battery systems for diverse applications (e.g., plug-in electric vehicles and hybrid locomotives). The underlying theory is built upon the concept of symbolic dynamics, which represents the behavior of battery system dynamics at different levels of SOC as probabilistic finite state automata (PFSA). In the proposed method, (finite-length) blocks of battery data are selected via wavelet-based segmentation from the time series of synchronized input–output (i.e., current–voltage) pairs in the respective two-dimensional space. Then, symbol strings are generated from the segmented time series pairs in the sense of maximum entropy partitioning and a special class of PFSA, called the D-Markov machine, is constructed to extract the features of the battery system dynamics for pattern classification. To deal with the uncertainties due to the (finite-length) approximation of symbol sequences, combinations of (a priori) Dirichlet and (a posteriori) multinomial distributions are respectively adopted in the training and testing phases of pattern classification. The proposed concept of pattern classification has been validated on (approximately periodic) experimental data that have been acquired from a commercial-scale lead-acid battery.
Batteries are key components in electric vehicles and energy storage systems. To estimate a battery’s state of charge, monitor its state of health, and formulate a balanced strategy, a battery model that requires a shorter and less costly study period than a real battery is established. This paper aims to describe a single-particle model of a lithium-ion battery that has a simple structure, can be embedded in simulation software for online applications, and provides a high-accuracy characterization of the dynamics. The single-particle model, which is described by a set of partial differential equations, is a simplified electrochemical model that characterizes the dynamic voltage response. A procedure for reducing the model based on the three-parameter polynomial approximation and the volume-average integration method is proposed to simplify the partial differential equations of the single-particle model. Identifying the parameters in the battery model is the key problem. The convergent bacterial foraging optimization algorithm with a short computation time is adopted for identifying the electrochemical parameters, including the active surface areas of the electrodes, the diffusion coefficients of the lithium ions in the solid phase, and the reaction rate constants. Then, the single-particle model of a lithium-ion battery is set up in MATLAB and Simulink. Finally, the precision of the single-particle model is verified by comparing the terminal voltages of the battery and the model. The results show that the single-particle model of a lithium-ion battery is very accurate and simple, thus verifying the reliability of the parameter identification process.
In this paper, we report that Sn-nanocluster-covered SnO2 nanowire (“hybrid architectures”) electrodes exhibited stage-wise de-lithiation suggesting complete lithium extraction. The lithiation and de-lithiation behavior explains that the high capacity retention of 814 mAh g−1 and durability over hundred cycles is because of low irreversible capacity loss. Mono-layers of un-agglomerated, sub 60 nm size Sn clusters supported on metallic electrodes also exhibited similar stage-wise de-lithiation while the microscale Sn clusters exhibited single-phase lithium extraction. This can be attributed to shorter lithium ion diffusion lengths and high surface area of the nanomaterials. The cyclic voltammetric studies of Sn nanoclusters (sub 60 nm size) confirm the reaction kinetics limited behavior of lithiation and de-lithiation characteristics. The Sn-nanocluster-covered SnO2 nanowires showed a capacity retention of 458 mAh g−1 at 500 mAg−1 current density indicating an excellent rate capability.
The poor cycling stability and large voltage decay in Li-rich cathode materials is related to the layer to spinel structural transformation. It is understood that the ease of structural transformation is correlated to the amount of oxygen gas released during the first charge above 4.5V. So one of the effective strategy to improve the electrochemical properties is by suppressing oxygen evolution through stabilizing oxygen radical intermediates by tuning metal-oxygen bond characteristics such as covalency, bond energy, iconicity, etc. through cation substitutions in Li rich phases. In this work we report that small amount of Ca substitution in Li layers of Li rich phases, Li1.2-2xCaxCo0.13Ni0.13Mn0.54O2 (x=0.005) improves the electrochemical cycling stability as well as the rate capability. With x=0.005 calcium substitution, the initial coulombic efficiency increased from 70% (for the pristine) to 83% and the capacity retention is improved from 71% to 87% after 100 cycles. Similarly Ca doping improves the rate capability especially at higher rates. The improved electrochemical performance of the Ca doped Li-rich cathode can be attributed to the fine-tuning of the crystal-chemical aspects manifested through enhanced structural stability and increased interlayer distance.
Extensive studies have reported cognitive abnormalities in neurodevelopmental disorders, such as autism spectrum disorder (ASD). Another line of evidence suggests that stress also affects cognitive functions. In this study, we investigated whether there were associations between stress hormones and cognitive functions in ASD and typically developing (TD) children. Cognitive functions in ASD and TD children were evaluated with a battery of psychological tests for working memory, behavioral flexibility, and social cognition for emotional assessments of others. ASD children exhibited higher hair and salivary cortisol, which reflects chronic and acute stress hormone levels of subjects, respectively, than TD children. Autism-spectrum quotient (AQ) was positively correlated with hair cortisol and the scores of Spence Children's Anxiety Scale in ASD children. In addition, a negative correlation was present between spatial working memory performance and hair cortisol in ASD, but not in TD, children. These results suggest that chronic stress hormone elevation may have relationships with some aspects of cognitive dysfunction in ASD subjects.
Mesoporous carbon (MC) spheres with hierarchical pores, controlled pore volume and high specific surface areas have been prepared by a mass-producible spray drying assisted template method using sodium alginate as carbon precursor and commercial colloidal silica particles as hard template. The resulting MC spheres, possessing hierarchical pores in the range of 3–30 nm, are employed as conductive matrices for the preparation of cathode materials for lithium–sulfur batteries. A high pressure induced one-step impregnation of elemental sulfur into the pore of the MC spheres has been exploited. The electrochemical performances of sulfur-impregnated MC spheres (S-MC) derived from MC spheres with different pore volume and specific surface area but with the same sulfur loading ratio of 60 wt% (S-MC-X-60) have been investigated in details. The S-MC-4-60 composite cathode material displayed a high initial discharge capacity of 1388 mAhg−1 and a good cycling stability of 857 mAhg−1 after 100 cycles at 0.2C, and shows also excellent rate capability of 864 mAhg−1 at 2C. More importantly, the sulfur loading content in MC-4 spheres can reach as high as 80%, and it still can deliver a capacity of 569 mAhg−1 after 100 cycles at 0.2C.
Longitudinal clinical investigations and biological measurements have determined not only progressive brain volumetric and functional changes especially around the onset of psychosis but also the abnormality of developmental pathways based on gene–environment interaction model. However, these studies have contributed little to clinical decisions on their diagnosis and therapeutic choices because of subtle differences between patients and healthy controls. A multi-modal approach may resolve this limitation and is favorable to explore the pathophysiology of psychosis. The integrative neuroimaging studies for schizophrenia targeting early intervention and prevention (IN-STEP) is a research project aimed at exploring the pathophysiological features of the onset of psychosis and investigating possible predictive biomarkers for the clinical treatment of psychosis. Since 2008, we have adopted blood sampling, neurocognitive batteries, neurophysiological assessment, structural imaging, and functional imaging longitudinally for help-seeking ultra-high-risk (UHR) individuals and patients with first-episode psychosis (FEP). Here, we intend to introduce the IN-STEP research study protocol and present preliminary clinical findings. Thirty-seven UHR individuals and 30 patients with FEP participated in this study. Six months later, there was no difference in objective and subjective scores between the groups, which suggests that young people having symptoms and functional deficits should be cared for regardless of their history of psychosis according to their clinical stages. The rate of transition to psychosis was 7.1%, 8.0%, and 35.3% (at 6, 12, and 24months, respectively). Through this research project, we expect to clarify the pathophysiological features around the onset of psychosis and improve the prognosis of psychosis through clinical application.
The computer simulation of the dissolution during discharge of silver electrodes in batteries and other devices with various silver-conducting solid electrolytes was carried out. The model of the pseudo-porous electrode represents small silver spheres, distributed in a solid electrolyte matrix. Various parameters simulated were: diameter of silver particles, silver to electrolyte relationship within the electrode, thickness of the electrode, conductivity of the electrolyte, discharge current and thickness of the separator. Calculated distribution of current in the electrode and the discharge curves at various parameters were obtained. A comparison of the calculated and experimental discharge curves was carried out. The good correspondence of these curves testifies to adequacy of the surveyed model of the dissolution of metal electrode for devices with solid electrolytes. Optimal parameters of the electrode are recommended depending on the use of these devices with solid electrolytes.
Goel et al found similar deficits in visual discrimination in humans and in a mouse model of FXS. In mice, a robust decrease in PV cell activity mediated this impairment, suggesting that manipulating inhibition may improve sensory processing in FXS.
In the present study we have shown that carbonaceous micro/macrocellular foams can be used for efficient and stable non-specific enzyme entrapment. In this context, Bilirubin Oxidase adsorbed into the porous electrode is able to reduce O2 to water and electrons are transferred directly from the electrode to the enzyme without the need of a redox mediator. The reduction current is stable for several days under continuous operation and therefore we consider the carbonaceous foams are very promising candidates for the construction of 3-dimensional biofuel cell cathodes. Mediator free, the electrode preparation and further enzyme adsorption are extremely simple, low cost and versatile. Most important, the excellent mechanical strength and the synthetic route allow us to design at will the size and external shape of the electrodes, which are of vital importance if we wish to incorporate electrodes into devices. The Integrative Chemistry synthetic route allows accessing hierarchical porosities with the advantage of specific functionalities. Macropores serve to fuel transport and micropores as anchoring sites for enzyme entrapment. Despite the inability to reach the Levich diffusion limited current suggesting that the porosity is not yet fully optimized, the results presented here show that porous carbonaceous foam electrodes allow for an incredible increase in enzyme loading which allows for a 500-fold current enhancement and stabilization of the direct electron transfer current from few hours to several days as compared to conventional flat electrodes.
A bifunctional ion-electron conducting layer is designed for all-solid-state lithium-sulfur battery. This layer consists of electronic conductor and solid polymer electrolyte that is intercalated between the cathode and electrolyte. By forming a gradient of electrons and lithium ions, the electrochemical performance and interfacial compatibility of the battery are obviously enhanced. When a pure sulfur powder is directly used as an active material of the cathode, the battery with the interlayer delivers the initial discharge capacity of 1457 mAh g−1 and the discharge capacity of 792.8 mAh g−1 after 50 cycles at 0.5 C and 80 °C, while the battery with the same cathode and without the interlayer only has the discharge capacity of 291.9 mAh g−1 after the same number of cycles.
The results obtained with solid electroactive microparticles immobilized on a graphite electrode surface using cyclic voltammetry and in situ microRaman measurements at selected potentials allowed us to complete the understanding of the spectroelectrochemical behaviours of Prussian blue, β-PbO and Bi2O3. In the case of Prussian blue, we provided a simple but complete analysis of the Raman spectral data for the species Fe[Fe(CN)6] and K2Fe[Fe(CN)6]. The investigation of PbO in neutral chloride media showed that Pb(OH)Cl is the Pb° electrochemical oxidation product whereas the study of Bi2O3 demonstrated that the oxidation of Bi° in alkaline solutions leads essentially to amorphous Bi(OH)3.
Mercury in the environment originates from both natural and anthropogenic sources. The latter, especially released from the use of fossil fuels, substantially surpasses the natural emissions. Mercury uses have resulted in occupational exposures in several occupations and nonoccupational exposure occurs mainly through the consumption of fish, a result of bioaccumulation and biomagnification of methylmercury. Adverse health effects depend on the degree of exposure and the kind of mercury in question, but children and the fetus are notably more susceptible, especially to methylmercury toxicity. Although exposure limits have been lowered, and some uses are being phased out, much remains to be done with respect to limiting human mercury exposure.
The influence of the solvent used in the processing of Li1.2Ni0.2Mn0.6O2 Li-rich electrodes has been thoroughly studied using complementary chemical, structural and electrochemical characterization techniques. Structural characterization has demonstrated that the bulk chemical composition and the structure of the material remain unchanged when processing the electrode in organic and aqueous media. 6Li solid state NMR measurements revealed that no perceptible variations of the signal positions and intensities were observed for the different samples, indicating the absence of H+/Li+ ionic exchange upon water exposition. Full coin-cells with the waterborne and organic processed Li-rich cathodes and graphite anodes delivered exceptional capacity retention during more than 250 cycles at 100% depth of discharge. This study proves that water-based binders can be used both for the anode and the cathode formulations of the next generation of Li-ion batteries.
To address the severe volume changes of transition metal chalcogenides that results in inferior cycling performance, herein, a unique yolk-shell microsphere composed of mesoporous cobalt sulfide yolk and alveolus-like carbon shell (M-CoS@C) is constructed. The mesoporous CoS yolks possess large surface area (46.3m2 g−1) accompanied with the interconnected mesoporous structure, which provide a large contact area to facilitate the permeation of the electrolyte and shorten the ion diffusion path. The alveolus-like carbon shells provide enough void spaces and highly self-adaptive structure to ensure the high stability of the electrode. Owing to the multifunctionality of this unique structure, the M-CoS@C electrode shows impressive cycling stability (790mAhg−1 after 500 cycles at 1Ag−1 for Li-storage, 532mAhg−1 after 100 cycles at 0.2Ag−1 for Na-storage) and excellent rate capability (330mAhg−1 at 20Ag−1 for Li-storage, 190mAhg−1 at 20Ag−1 for Na-storage). This unique mesoporous yolks@alveolus-like carbon shell structure and the self-sacrificing synthesis method present the effective strategies to promote the utilization of transition metal chalcogenides for practical applications.
Hydrated vanadium pentoxide (V2O5·0.86H2O) nanoribbons modified with reduced graphene oxide (RGO) are synthesized by a hydrothermal process. These ribbons are 30 nm thick, 200 nm to 1 μm wide and above 50 μm long. Binder-free films are prepared by using these ribbons and annealed at 300 °C in nitrogen as the cathode for rechargeable lithium cells. The intertwining network of this free-standing VO x /RGO film provides efficient conduction pathways for electrons and short diffusion distances for Li ions. The electrochemical tests exhibit that this cathode film delivers a high reversible specific capacity (160 mAh g−1) and good cycling stability (133 mAh g−1 after 200 cycles) in the voltage range between 2.0 and 3.5 V.
Palladium (Pd) is a metal frequently used for dental alloys. In order to elucidate controversial options about Pd concerning its biological performances, our study consists in the evaluation of commercial and experimental PFM and C&B precious and semi-precious dental alloys. This investigation was also designated to the establishment of a cytotoxicity index (CI) such as it was described for hemocompatibility testing. The following materials were tested: 36 commercial alloys (Au-, Pd- and Ag-base), 14 experimental alloys (Pd-base established by an experience plan) and pure metals (Ag, Au, Cu, Ni, Cr, In, Sn, Pt, Ti, Zn). The cells culture experiments were carried out with epithelial L132 cells and NIH 3T3 fibroblasts. In vitro cell viability tests show that Pt, Sn, In, Ti, Au and Pd have no cytotoxic effect; Cr, Cu and Ag are toxic, Ni, Zn, and Co are highly toxic. An identical ranking was found with the inflammatory and proliferation tests. Toxic and highly toxic metals induced slight or strong prosthetic dental restoration morphological alterations after 3-days cultures and mostly cell death after 6-days cultures. These effects are dependent on the leakage of the element into the culture medium as revealed by ICP. The addition of Au gives benefit to Pd–Ag alloys, but does not produce any major effect on Pd–Cu alloys. This qualitative ranking can quantitatively be confirmed by cytocompatibility testing after application of a CI.
In this work, the effects of modifications in the synthesis Li/Co/dopant concentrations on the performance and cycle life of lithium cobalt oxide are investigated to learn how different modification methods work in relation to each other and to provide data for up-to-date commercial interest. The LiCoO2 materials are prepared using the same precursors and synthesis process to ensure the comparability. The electrochemical characterizations are performed in both half-cells and LiCoO2/graphite pouch cells. The Mg–Ti doped LiCoO2 shows superior performance compared to stoichiometric and over-lithiated LiCoO2. The Mg–Ti doped sample shows 89% capacity retention after 1000 cycles in 3.0–4.2 V and 80% capacity retention after 240 cycles in 3.0–4.4 V in LiCoO2/graphite pouch cell. The better rate capability is attributed to Ti doping reducing the Co valence in LiCoO2, making it more metallic and conductive. The longer cycle life of the doped LiCoO2, in turn, is attributed to a better structural stability caused mainly by Mg doping. This is also reflected in a smaller increase in the charge transfer impedance during cycling. In contrast, the Li doping increases the material impedance and thus decreases the cycle life of the material.
Composites containing conductive polymers and Au and Ag nanoparticles were introduced into the environmentally sensitive poly(N-isopropylacrylamide) hydrogel channels. The composites were synthesized directly in the channels by two phase polymerization procedure. In the first step the unmodified hydrogel was placed in a solution containing the oxidizing agent (HAuCl4 or AgNO3), and in the second step it was placed in a solution of aniline in nitrobenzene. The presence of polyaniline and metal nanoparticles increased conductivity of both types (ionic and electron) while the hydrogel properties, such as: flexibility, plasticity and ability to phase transition, were preserved. The presence of nobel-metal nanostructures added catalytical activity to the new materials. Optical and SEM investigations revealed that polymer-metal composites were uniformly distributed in the entire gel samples. NIPA-PANI-Au composites exhibited a sharp volume phase transition in response to changes in temperature and ionic strength. That behavior was similar to unmodified poly (N-isopropylacrylamide) hydrogel. The new material was electroactive and had electrocatalytical properties towards electrooxidation of ethanol. Electroactivity of the modified gel was a strong function of the swelling ratio; the shrinking process enhanced the voltammetric response.