batterydata/paper-abstracts huggingface dataset:
Recent results, part of an ongoing research programme aimed to develop synthetic methods which could be used to functionalise conducting polymers, are described. Among those methods are the copolymerization of aniline with substituted anilines and post-modification reactions of polyaniline, such as: electrophilic substitution, nucleophilic addition and coupling with diazonium salts. Some of those methods could be chemically or electrochemically controlled allowing a quantitative tailoring of the modification. The effect of the added functionalities on the electrochemical properties of the polymers is investigated using spectroscopic and electrochemical techniques. The extension of the synthetic methods to combinatorial modification of conductive polymers is also discussed.
Li3PO4 coated Li1.18Co0.15Ni0.15Mn0.52O2 cathode materials were prepared by the precipitation method. The Li3PO4 coating process cleans the Li2CO3 impurity on the surface of the material. In addition, a continuous stacking faults region forms in the near-surface region of the material. Electrochemical studies show that Li3PO4 coating improves the activation of Mn4+ ions, prohibits the growth of solid electrolyte interface film and facilitates the charge transfer reactions at the electrode/electrolyte interface. As a result, the Li3PO4 coated materials show larger discharge capacities, longer cycle life and better rate capability than the un-coated one. With the coating content as small as 1.0wt%, the material shows a high discharge capacity of 272.5mAhg−1 at the 0.4C rate and 121.1mAh g−1 at the 10C rate. The capacity fading rate at 0.4C is only 0.08 % per cycle. Differential scanning calorimetry shows that the exothermic temperature of the fully charged electrode increases from 203.0°C to 289.7°C after Li3PO4 coating. And the thermal release reduces from 832.4Jg−1 to 305.5Jg−1 highlighting the improved thermal stability of the Li3PO4 coated material.
This study investigated changes in glycemic control following a small increase in time spent outdoors. Women participants with type 2 diabetes (N = 46) wore an iBUTTON temperature monitor and a pedometer for 1 week and recorded their morning fasting blood glucose (FBG) daily. They went about their normal activities for 2 days (baseline) and were asked to add 30 min of time outdoors during Days 3–7 (intervention). Linear mixed effects models were used to test whether morning FBG values were different on days following intervention versus baseline days, and whether steps and/or heat exposure changed. Results were stratified by indicators of good versus poor glycemic control prior to initiation of the study. On average, blood glucose was reduced by 6.1 mg/dL (95% CI − 11.5, − 0.6) on mornings after intervention days after adjusting for age, BMI, and ambient weather conditions. Participants in the poor glycemic control group (n = 16) experienced a 15.8 mg/dL decrease (95% CI − 27.1, − 4.5) in morning FBG on days following the intervention compared to a 1.6 mg/dL decrease (95%CI − 7.7, 4.5) for participants in the good glycemic control group (n = 30). Including daily steps or heat exposure did not attenuate the association between intervention and morning FBG. The present study suggests spending an additional 30 min outdoors may improve glycemic control; however, further examination with a larger sample over a longer duration and determination of mediators of this relationship is warranted.
The self-discharge process of vanadium flow battery (VFB) assembled with Nafion 115 is investigated in very detail for the first time. The self-discharge phenomenon of VFB is closely related to the diffusion coefficients of the vanadium ions, which are found to be in the order of V2+ >VO2+ >VO2 + >V3+. Five regions on the change of open circuit voltage (OCV) are clearly found during the self-discharge process. The regions include three platforms and two obvious decreasing regions. VO2 + disappears in the second region, while the V2+ disappears in the fourth one. In the first three regions, the self-discharge reactions at the positive and negative side are different, owing to the crossover of vanadium ions. In the last two regions, the changes of vanadium ions are derived from the diffusion of V3+ and VO2+ at positive and negative electrolyte. The self-discharge process at different flow rates or different state of charge (SOC) is also investigated, indicating that the self-discharge time shortens with increasing of flow rate between 40 and 80 mL/min or decreasing of the initial SOC. This paper will provide very valuable information for the relaxation or elimination of self-discharge phenomenon of VFB, which is one of the most troublesome issues in VFB application.
Bioassays were carried out to study the differences in cadmium (Cd) toxicity to premetamorphic tadpoles of Rhinella arenarum, in aqueous solutions with variable contents of calcium in the presence and absence of humic acids, and to analyze the relationship between the free Cd2+ ion concentrations calculated by chemical modeling and the biological results. The correlation analysis of the free Cd2+ concentration calculated by chemical speciation and the analytical Cd yielded a direct relationship between the degree of toxicity and the slope value. The lowest slope was obtained from the treatments with lowest free Cd2+ ion concentration and lowest toxicity, whereas the highest slope was obtained from the most toxic treatment. At comparable concentrations of free Cd2+, intralarval Cd increased as the Ca in the solution decreased. At equal contents of Ca, in the presence of humic acids, the content of Cd in larvae was higher and the toxicity values lower. The results obtained in this study show that waterborne Ca could offer some protection from metal uptake and accumulation by competitive inhibition in the uptake mechanism that involves active transport via cell membrane. In the systems with humic materials, a certain proportion of the Cd present in the solution was associated to them and thus became less bioavailable.
Solid-state batteries (SSBs) with metallic lithium (Li) anodes and nonflammable solid-state electrolytes (SSEs) are viewed as the next-generation batteries because of their potential improvement in energy density and guarantee of safety. However, even though the high-density solid garnet SSE pellets exhibit high ionic conductivity, high transference number, and large shear modulus, the unexpectedly serious occurrence of dendrite propagation remains a problem. Herein, a mixed conductive layer (MCL) consisting of electron-conductive nanoparticles embedded in an ion-conductive network is introduced at the interface between the garnet SSE and the Li anode. Such MCL not only leads to the transition from lithiophobicity to lithiophilicity, but also homogenizes the electric-field distribution inside the MCL and relieves the electronic attacks to the garnet. As a result, the Li/MCL/garnet/MCL/Li cells show a critical current density as high as 1.2 mA cm−2 and stable cycling for over 1000 h at 0.1 mA cm−2. The LiCoO2/Li cells with the MCL-protected interface show excellent cycling and rate performance at room temperature. These results demonstrate a rational design for a stable garnet/Li interface and an effective strategy to enable Li metal anodes in SSBs.
This study examines how information regarding poverty influences support for redistribution. Redistributive policies involve allocating resources to address poverty and inequality. Previous research finds that support for redistributive policies is grounded in attitudes towards government size, social mobility, partisan identity, and political ideology. In this study, we test how information regarding poverty impacts support for redistributive policies. When subjects are given information about the material well-being of those in poverty, we expect to find less support for redistributive policies. On the other hand, when subjects are presented with information about the effect of poverty on the decision-making of those in poverty, we expect to find greater support for redistribution. Using survey experiments with undergraduate subjects from a public university in the southern region of the United States, we find no differences in support for redistributive policies in response to these two types of information.
Hybridization is a widespread phenomenon, which plays crucial roles in the speciation of living beings. However, unnatural mixing of historically isolated taxa due to human-related activities has increased in recent decades, favouring levels of hybridization and introgression that can have important implications for conservation. The wild red-legged partridge (Alectoris rufa, Phasianidae) populations have recently declined and the releases of farm-reared partridges have become a widespread management strategy. The native range of the red-legged is limited to the south-west of Europe (from Italy to Portugal). This species does not breed in sympatry with the chukar partridge (A. chukar), whose range is Eurasian (from Turkey to China). However, red-legged partridges have often been hybridized with chukar partridges to increase the productivity of farmed birds, and game releases may have spread hybrid birds into the wild. In this study, we investigated the fitness (survival and breeding) differences between hybrid and “pure” red-legged partridges in a wild population located in central Spain. Incubation probability was similar in hybrids and “pure” partridges. Hybrid females laid larger clutches than “pure” ones, but hatching success did not differ between hybrid and “pure” partridges. Hybrid birds had lower survival rate than “pure” ones, mainly because of higher predation rates. Our results show that, despite lower survival, hybrid partridges breed in natural populations, so this could increase extinction risk of wild pure partridge populations, through releases of farmed hybrid birds. The consequences of continued releases could be of vital importance for the long term conservation of wild red-legged partridges.
Li-rich layered cathode materials have received wide attention due to their superior Li-storage capability. However, their applications are still limited by capacity degradation and voltage decay, which is caused by the phase transition and metal dissolution during repeated cycling. In this work, iron oxide (FeOx) atomic layer deposition (ALD) was performed on Li-rich layered cathode powders in a fluidized bed reactor, followed by an annealing process to further improve their electrochemical performance. After 100 cycles of charge-discharge at 55 °C and 1C (1C = 250 mA g−1), the cathode made from particles with 40 cycles of FeOx ALD and annealing showed a 73% retention of the initial capacity (221 mAh g−1), while the electrode made from the pristine powders showed only 26% retention of the initial capacity (197 mAh g−1) at the same conditions. The enhancement of Li+ transport and cyclic stability stemmed from a stable Fe-doped spinel phase on the surface of cathode particles after ALD coating followed by annealing. A detailed post-test analysis demonstrated that the modification limited impedance growth and suppressed electrolyte degradation and metal dissolution.
Oligomeric Schiff bases with carboxylate end-groups are crystalline, electrochemically active materials at voltages below 1.2 V vs. Na+/Na. This low redox voltage along with delivered capacities up to 340 mA h g−1 makes them potential anode materials for sodium ion batteries. The electrochemical performance is optimized by maximizing the number of active units with respect to the total chain length. We report for the first time the electrochemical activity of the 10-π-electron end group (–−OOC–ϕ–CN–) (ϕ refers to the phenyl group) and central (–NC–ϕ–CN–) Hückel units. This enhanced activity is due to the larger stability of planar molecular regions with respect to out-of-plane inactive (–−OOC–ϕ–NC–) and (–CN–ϕ–NC–), as confirmed by DFT calculations.
Developing an understanding of structure–activity relationships and reaction mechanisms of catalytic processes is critical to the successful design of highly efficient catalysts. As a fundamental reaction in fuel cells, elucidation of the oxygen reduction reaction (ORR) mechanism at Pt(hkl) surfaces has remained a significant challenge for researchers. Here, we employ in situ electrochemical surface-enhanced Raman spectroscopy (SERS) and density functional theory (DFT) calculation techniques to examine the ORR process at Pt(hkl) surfaces. Direct spectroscopic evidence for ORR intermediates indicates that, under acidic conditions, the pathway of ORR at Pt(111) occurs through the formation of HO2*, whereas at Pt(110) and Pt(100) it occurs via the generation of OH*. However, we propose that the pathway of the ORR under alkaline conditions at Pt(hkl) surfaces mainly occurs through the formation of O2−. Notably, these results demonstrate that the SERS technique offers an effective and reliable way for real-time investigation of catalytic processes at atomically flat surfaces not normally amenable to study with Raman spectroscopy.
Selected energy and material resource conversion systems are compared in this paper under an extended LCA point of view. A multi-method multi-scale assessment procedure is applied in order to generate consistent performance indicators based on the same set of input data, to ascertain the existence of constraints or crucial steps characterized by low conversion efficiency and to provide the basis for improvement patterns. Optimizing the performance of a given process requires that many different aspects are taken into account. Some of them, mostly of technical nature, relate to the local scale at which the process occurs. Other technological, economic and environmental aspects are likely to affect the dynamics of the larger space and time scales in which the process is embedded. These spatial and time scale effects require that a careful evaluation of the relation between the process and its surroundings is performed, so that hidden consequences and possible sources of inefficiency and impact are clearly identified. In this paper we analyse and compare selected electricity conversion systems, alternative fuels and biofuels, waste management strategies and finally the time evolution of an urban system, in order to show the importance of a multiple perspective point of view for the proper evaluation of a system's environmental and resource use performance.
Although it is widely assumed that children with learning disabilities have “sequencing problems,” these have not been well specified. A non-verbal serial reaction time (SRT) paradigm was used to evaluate motor sequence learning in 422 children between ages 7 and 11 in relation to reading, cognitive ability level, and attention problems. The children demonstrated the response profile typically associated with motor sequence learning, but the component of the profile indicative of implicit sequence learning was not reliably associated with any of the predictors. Cognitive ability predicted overall response time; cognitive ability, reading, and attention problems each predicted overall accuracy. Explicit learning was predicted by cognitive ability, but not by reading or attention problems. Thus, we found no evidence that poor reading is preferentially associated with a domain general deficit in sequential learning.
Abnormal microstructural integrity and glucose metabolism of the hippocampus are common in subjects with Alzheimer’s disease (AD) that typically manifest as episodic memory impairment. The above-tissue alterations can be captured in vivo using diffusion tensor imaging (DTI) and positron emission tomography with [18F]fluorodeoxyglucose (FDG-PET). Here, we explored relationships between the above neuroimaging and cognitive markers of early AD-specific hippocampal damage. Twenty patients with early AD (MMSE 25.7 ± 1.7) were studied using DTI and FDG-PET. Episodic memory performance was assessed using the free delayed verbal recall task (DVR). In the between-modality correlation analysis, FDG uptake was strongly associated with diffusivity in the left anterior hippocampus only (r = −0.81, p < 0.05 Bonferroni’s corrected for multiple tests). Performance on DVR significantly correlated with left anterior (r = −0.80, p < 0.05) and left mean (r = −0.72, p < 0.05) hippocampal diffusivity, while the correlation with left anterior FDG uptake did not reach statistical significance (r = 0.52, n.s.). DTI-derived diffusivity of the anterior hippocampus might be a sensitive early marker of hippocampal dysfunction as reflected at the synaptic and cognitive levels. This neurobiological distinction of the anterior hippocampus might be related to the disruption of the perforant pathway that is known to occur early in the course of AD.
The combination of a sodium-nickel chloride (ZEBRA) battery and intermediate temperature solid oxide fuel cell (IT-SOFC) to form a hybrid power system intended for automotive applications is examined with the aid of a fuel cell system model. The model allows the operating temperatures of the system to be assessed with a view to thermal integration with the battery. Efficiency curves for stacks and systems are described along with the temperature distribution around the system. Two types of IT-SOFC are compared, one operating in the 500–650°C temperature region and one in the 700–850°C region. The lower temperature IT-SOFC using external steam reforming, and the higher temperature system using partial internal steam reforming, both of methane fuel.
A positive association between brain size and intelligence is firmly established, but whether region-specific anatomical differences contribute to general intelligence remains an open question. Results from voxel-based morphometry (VBM) - one of the most widely used morphometric methods - have remained inconclusive so far. Here, we applied cross-validated machine learning-based predictive modeling to test whether out-of-sample prediction of individual intelligence scores is possible on the basis of voxel-wise gray matter volume. Features were derived from structural magnetic resonance imaging data (N = 308) using (a) a purely data-driven method (principal component analysis) and (b) a domain knowledge-based approach (atlas parcellation). When using relative gray matter (corrected for total brain size), only the atlas-based approach provided significant prediction, while absolute gray matter (uncorrected) allowed for above-chance prediction with both approaches. Importantly, in all significant predictions, the absolute error was relatively high, i.e., greater than ten IQ points, and in the atlas-based models, the predicted IQ scores varied closely around the sample mean. This renders the practical value even of statistically significant prediction results questionable. Analyses based on the gray matter of functional brain networks yielded significant predictions for the fronto-parietal network and the cerebellum. However, the mean absolute errors were not reduced in contrast to the global models, suggesting that general intelligence may be related more to global than region-specific differences in gray matter volume. More generally, our study highlights the importance of predictive statistical analysis approaches for clarifying the neurobiological bases of intelligence and provides important suggestions for future research using predictive modeling.
In this preliminary study, we tried to use sodium polyacrylate as the super absorbent polymer to form alkaline NaBH4 gel and explored its possibilities for borohydride hydrolysis and borohydride electro-oxidation. It was found that the absorption capacity of sodium polyacrylate decreased with increasing NaBH4 concentration. The formed gel was rather stable in the sealed vessel but tended to slowly decompose in open air. Hydrogen generation from the gel was carried out using CoCl2 catalyst precursor solutions. Hydrogen generation rate from the alkaline NaBH4 gel was found to be higher and impurities in hydrogen were less than that from the alkaline NaBH4 solution. The NaBH4 gel also successfully powered a NaBH4-air battery.
We report the largely improved electrochemical capacitance of polypyrrole-derived microporous carbon nanospheres (MCNs, 80–100 nm in diameter) containing nitrogen functional groups. We have investigated the electrochemical properties of precursor polypyrrole nanospheres (PNs, with a high N/C ratio and low surface area) and as-derived carbon nanospheres (CNs, with a moderate N/C ratio and low surface area) prepared by carbonizing PNs at different temperatures, and MCNs (with a low N/C ratio and high surface area) obtained by chemical activation of CNs. The samples are thoroughly characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, thermogravimetric analysis (TGA), nitrogen sorption, elemental analysis, and X-ray photoelectron spectroscopy (XPS). It is found that MCNs with a high surface area and N-doping species exhibit much better capacitive performance compared to the PNs and CNs, and commercial carbon blacks (XC-72 and BP2000) as well. The MCN sample gives a reversible specific capacitance of ∼240 F g−1 for 3000 cycles in aqueous media as a result of combined advantages of high electrochemical activity of doped heteroatoms (N and O) and accessible well-developed porosity, demonstrating the promising use in high-energy-density supercapacitors.
Structural evolution during topotactical electrochemical lithium insertion and deinsertion reactions in ramsdellite-like Li x Ti2O4 has been followed by means of in situ X-ray diffraction techniques. The starting Li x Ti2O4 (x =1) exists as a single phase with variable composition which extends in the range 0.50≤ x ≤1.33. However, beyond the lower and upper compositional limits, two other single phases, with ramsdellite-like structure, are detected. The composition of these single phases are: TiO2 upon lithium deinsertion and Li2Ti2O4 upon lithium insertion. Both TiO2 and Li2Ti2O4 are characterized by narrow compositional ranges. The close structural relationship between pristine LiTi2O4 and the inserted and deinserted compounds together with the relative small volume change over the whole insertion–deinsertion range (not more than 1.1% upon reduction) is a guaranty for the high capacity retention after long cycling in lithium batteries. The small changes in cell parameters well reflect the remarkable flexibility of the ramsdellite framework against lithiation and delithiation reactions.
As a consequence of developing information and communication technology that is playing a significant role in our society and has changed our life dramatically, we witnessed a significant increase in energy consumption in computer systems and networks. Subsequently, energy harvesting technologies with renewable energy are of great interest in the field of computer systems and networks, and thus lead to abundant research which has been carried out to address energy harvesting from different aspects. However, the majority of them focuses on wireless or small-scale networks, which left wired networks with a general structure neglected. We first present a comprehensive systemic review of the trends of overall energy consumption, and energy and quality of service optimization in computer systems and networks. Then, this paper reviews the recent research progress in G-networks and energy packet networks with renewable and intermittent energy from both the system paradigms and the performance optimization and energy reduction algorithms for the wired networks.