batterydata/paper-abstracts huggingface dataset:
Stress is one of the key factors leading to capacity fading and triggering safety issues in lithium-ion batteries. In this paper, the stress in layered electrodes during the electrochemical process is investigated. Considering the electrochemically induced changes in the elastic modulus of the electrode material, a stress model is established to obtain a modified Stoney stress equation. In addition, in situ bending deformation of the Si composite electrode during lithiation and delithiation is measured to be determined as a function of Li concentration. Combined with the established stress model, the lithiation-induced stress in the Si composite electrode material is quantitatively characterized. It is shown that the maximum compressive stress is 8.53 MPa. Furthermore, the differences between the established stress model and the classical Stoney stress equation are compared and discussed. Lithiation results in softening of the Si composite electrode material, which affects the stress during lithiation. The experimental results clearly demonstrate that softening of the Si composite electrode material significantly decreases and alleviates the stress.
The present study aimed to quantify cross-linguistic modulations of the contribution of phonemic awareness skills and visual attention span (VA Span) skills (number of visual elements that can be processed simultaneously) to reading speed and accuracy in 18 Spanish-French balanced bilingual children with and without developmental dyslexia. The children were administered two similar reading batteries in French and Spanish. The deficits of the dyslexic children in reading accuracy were mainly visible in their opaque orthography (French) whereas difficulties indexed by reading speed were observed in both their opaque and transparent orthographies. Dyslexic children did not exhibit any phonemic awareness problems in French or in Spanish, but showed poor VA Span skills compared to their control peers. VA span skills correlated with reading accuracy and speed measures in both Spanish and French, whereas phonemic awareness correlated with reading accuracy only. Overall, the present results show that the VA Span is tightly related to reading speed regardless of orthographic transparency, and that it accounts for differences in reading performance between good and poor readers across languages. The present findings further suggest that VA Span skills may play a particularly important role in building-up specific word knowledge which is critical for lexical reading strategies.
The large amount of data collected during a typical operando X-ray absorption fine structure (XAFS) experiment and the interest to thoroughly investigate and comprehend a redox process occurring in a Li-ion battery need an advanced data analysis approach. In this context, multivariate curve resolution (MCR) has gained attention as chemometric technique that allows the identification of the number of the species and their existence range without any a priori information on the studied system. The call for an advanced data treatment is answered by a joint XAFS-MCR approach, able to unveil the local structural dynamics of the selected species, providing a quick and efficient data interpretation.
Publisher Summary Mobile telephony has become a part of adolescents' everyday life. The mobile telephone is used for the functional coordination of family and peer interaction; it is used by parents to allay their fear that their child is in trouble and out of reach; and it is used to tie the peer group together. Adolescents use mobile telephone to ensure that they are accessible and in demand. Within economic constraints, it allows expressive integration and enables them to participate in “gifting,” as seen in the sending and receiving of telephone calls and text messages. The mobile telephone has impact on the breadth and depth of a teen's social network, and it allows for the quantification of popularity as seen in the number of names recorded in the device and the number of messages and calls received. Finally, ownership of the “correct” type of mobile telephone shows that teens are aware of the current fashion and that they are active in the creation and maintenance of their own identity. The symbolic value of the mobile telephone often precedes its actual possession. While there is a growing “functional” need for the mobile telephone as adolescents move into the midteen years, it is also seen as an object of desire by those who are still preadolescents.
We report the synthesis and Li-cyclability of α-Fe2O3 nanospindles derived from Fe based metal organic framework (MOF). Presence of phase pure structure and nanospindle morphology is investigated through XRD and SEM/TEM analysis, respectively. Half-cell, Li/α-Fe2O3 delivered reversible capacity of ∼1024mAhg−1 at current density of 100mAg−1 and showed excellent cyclability with capacity retention of over 90% after 40 galvanostatic cycles. Further, MOF derived α-Fe2O3 nanospindles are capable of delivering good reversible capacity under high current cycling. This clearly reveals that, MOF is one of the unique approaches to yield high performance iron oxide anodes and this approach can be extended to other transition metal oxides to develop high performance electrode materials.
Objective To evaluate the efficiency of an implanted chip system for the control of heart rate (HR). Methods The HR was recorded in six conscious Sprague-Dawley (SD) rats. An implanted chip system was designed to regulate the HR by stimulating the right cervical vagus nerve according to the feedback of real time HR. Each rat was subjected to 30-min regulation and 30-min recovery. The change of HR during the regulation period was compared with the control. The ECG was recorded during the experiment for 24 h. Results The ECG signals were successfully recorded during the experiment. The HR was significantly decreased during the period of regulation compared with control (−79.3 ± 34.5, P < 0.01, n = 6) and then recovered to normal after regulation. Conclusion The described implanted chip system can regulate the HR to a designated set point.
Lithium-ion cells, especially when used in electric vehicles at varying operation conditions, require a sophisticated battery management to ensure an optimal operation regarding operation limits, performance, and maximum lifetime. In some cases, the best trade-off between these conflictive goals can only be reached by considering internal, non-measurable cell characteristics. This article presents a data-driven model-reduction method for a strict electrochemical model. The model describes the charging process of a lithium-ion cell and possibly occurring degradation effects in a large temperature range and is presented in Part I of this contribution. The model-reduction process is explained in detail, and the gained model is compared to the original electrochemical model showing a very high approximation quality. This reduced model offers a very low computation complexity and is therefore suitable for the implementation in a battery management system (BMS). Based on this model, an advanced charging strategy is presented and evaluated for possible reductions in charging times especially at low temperatures.
A novel thin-film electrode was prepared by pencil-drawing on a ceramic state electrolyte, and was applied in a Li–air battery as a natural catalytic electrode of oxygen. This provides a snapshot of future Li–air batteries.
Marine ecosystem models that incorporate fisheries and climate change are essential for forecasting and guiding sustainable ecosystem management decisions. A key challenge in developing and applying ecosystem models that are able to provide robust predictions for management is to accurately represent the structure and dynamics of food webs. Ecosystem models vary in complexity and formulation and there is no set method routinely used to evaluate the skill of a model to correctly represent food web characteristics. One approach for evaluation is the comparison of modelled food web attributes with measures of stable isotope composition of taxa. While this approach has been used in some studies, its full potential has not been realised. Critically, directly modelling the assumed underlying processes that give rise to stable isotope signatures in ecosystem models has only just begun to be explored. Here, we examine the process of building ecosystem models and assess the potential for incorporating stable isotope results into this process, including the evaluation of model skill. We consider both size- and species- based ecosystem modelling approaches for their potential in this regard. We discuss that whilst conceptually achievable, in practice this is highly challenging through highlighting the advances and challenges in using stable isotope data, including the implications of precision associated with isotope-based measurements. We conclude with a proposed framework for explicitly integrating stable isotope data into both size- and species- based ecosystem models as an example of how signatures may be more powerfully used in the modelling process, and highlight key needs for future work.
Photovoltaic energy has nowadays an increased importance in electrical power applications, since it is considered as an essentially inexhaustible and broadly available energy resource. However, the output power provided via the photovoltaic conversion process depends on solar irradiation and temperature. Therefore, to maximize the efficiency of the photovoltaic energy system, it is necessary to track the maximum power point of the PV array. The present paper proposes a maximum power point tracker (MPPT) method, based on fuzzy logic controller (FLC), applied to a stand-alone photovoltaic system. It uses a sampling measure of the PV array power and voltage then determines an optimal increment required to have the optimal operating voltage which permits maximum power tracking. This method carries high accuracy around the optimum point when compared to the conventional one. The stand-alone photovoltaic system used in this paper includes two bi-directional DC/DC converters and a lead-acid battery bank to overcome the scare periods. One converter works as an MPP tracker, while the other regulates the batteries state of charge and compensates the power deficit to provide a continuous delivery of energy to the load. The Obtained simulation results show the effectiveness of the proposed fuzzy logic controller.
The effects of sodium additive on the microstructure and electrochemical properties of Li[Li0.2Mn0.54Ni0.13Co0.13]O2-based material have been investigated. XRD patterns show that the sodium additive doesn't incorporate into the Li[Li0.2Mn0.54Ni0.13Co0.13]O2 lattice, but induces a dispersed secondary phase with the structure of Na0.7MnO2.05. The two-phase composite shows an improved rate performance in comparison with the single phase of Li[Li0.2Mn0.54Ni0.13Co0.13]O2, which can be attributed to the enhanced electrical conductivity and lithium ion diffusion. The interfaces between Li[Li0.2Mn0.54Ni0.13Co0.13]O2 and the secondary phase provide fast diffusion paths for Li+. DC electrical conductivity and EIS are used to elucidate the phenomenon.
ABSTRACT The side reactions of LiO2, Li2O2 and Li2O, formed during the discharge process at the cathode/electrolyte interphase, are still a main challenge of lithium-air batteries. During these reactions, polyvinylidene difluoride (PVdF), as the commonly used cathode binder material, is decomposing, leading to a shorter lifetime of the battery. In this paper, we introduced and investigated polyisobutylene (PIB), a chemically and electrochemically inert polymeric material, to substitute PVdF as binder for lithium-air batteries. Results obtained by X-ray diffraction and spectroscopic methods showed, that PIB is far more stable in the presence of O2 −, O2 2− as well as O2− species compared to PVdF. This distinct inertness makes PIB a promising binder for lithium-air batteries.
As a promising substitute for fossil fuels, hydrogen has emerged as a clean and renewable energy. A key challenge is the efficient production of hydrogen to meet the commercial-scale demand of hydrogen. Water splitting electrolysis is a promising pathway to achieve the efficient hydrogen production in terms of energy conversion and storage in which catalysis or electrocatalysis plays a critical role. The development of active, stable, and low-cost catalysts or electrocatalysts is an essential prerequisite for achieving the desired electrocatalytic hydrogen production from water splitting for practical use, which constitutes the central focus of this review. It will start with an introduction of the water splitting performance evaluation of various electrocatalysts in terms of activity, stability, and efficiency. This will be followed by outlining current knowledge on the two half-cell reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), in terms of reaction mechanisms in alkaline and acidic media. Recent advances in the design and preparation of nanostructured noble-metal and non-noble metal-based electrocatalysts will be discussed. New strategies and insights in exploring the synergistic structure, morphology, composition, and active sites of the nanostructured electrocatalysts for increasing the electrocatalytic activity and stability in HER and OER will be highlighted. Finally, future challenges and perspectives in the design of active and robust electrocatalysts for HER and OER towards efficient production of hydrogen from water splitting electrolysis will also be outlined.
A Correction to this paper has been published: https://doi.org/10.1038/s41560-021-00819-4.
Carbon coated porous hollow Na2FePO4F (C/Na2FePO4F) spheres with 500 nm diameter and 80 nm wall thickness are synthesized by a one-step template-free ultrasonic spray pyrolysis process using sucrose as the carbon source. Nano-sized porous hollow C/Na2FePO4F spheres allow electrolyte to penetrate into the hollow structure, and thus the electrochemical reaction can take place on both the outside and inside surface and in the pores. Also, the carbon coating on Na2FePO4F hollow spheres enhances the electronic conductivity and charge transfer reaction kinetics. The unique carbon coated porous hollow C/Na2FePO4F cathodes deliver 89 mAh g−1 capacity at a low rate of 0.1C, and 75 mAh g−1 at 1C, and maintains 33% of capacity at 9C. After 750 cycles at 1C, C/Na2FePO4F cathodes can still provide 60 mAh g−1, which is 80% of initial capacity. The significant advance in electrochemical performance of hollow C/Na2FePO4F spheres combined with mature aerosol spray synthesis technology make these carbon coated porous hollow C/Na2FePO4F spheres very promising as cathode materials for practical applications in Na-ion batteries.
Graphene nanosheets are deposited on nickel foams with 3D porous structure by an electrophoretic deposition method using the colloids of graphene monolayers in ethanol as electrolytes. The high specific capacitance of 164Fg−1 is obtained from cyclic voltammetry measurement at a scan rate of 10mVs−1. When the current densities are set as 3 and 6Ag−1, the specific capacitance values still reach 139 and 100Fg−1, respectively. The high capacitance is attributed to nitrogen atoms in oxidation product of p-phenylene diamine (OPPD) adsorbed on the surface of the graphene nanosheets. The comparable results suggest potential application to electrochemical capacitors based on the graphene nanosheets.
Publisher Summary This chapter explains the concepts of fault-finding and testing. There is no right or wrong way to fault-find in instrument loops and systems. There are however, safe and potentially unsafe ways that are of the greatest importance to consider. The chapter aims to discuss the approach to fault-finding in such a way that guidance can be given on what shall and shall not be done from an explosion-protection safety point of view. The approach is described here such that the areas where aspects of safety must be considered can be clearly identified. This is one of the possible ways of proceeding; it is not a standard recommendation but is distilled from good engineering practice and experience in very general terms. The testing of the different types of IS interface will be examined. The testing discussed concerns functional operation, as the integrity of the safety protection cannot be verified without access to internal components. If an IS-certified installed apparatus is tested on site, it will not reveal the condition or status of explosion protection. Testing is not a specific requirement of the codes of practice where the test is not able to check the protection integrity. Unnecessary testing is not substantially useful and can cause more harm than good.
The Environmental Influences on Child Health Outcomes (ECHO) Program will evaluate environmental factors affecting children’s health (perinatal, neurodevelopmental, obesity, respiratory, and positive health outcomes) by pooling cohorts composed of >50,000 children in the largest US study of its kind. Our objective was to identify opportunities for studying chemicals and child health using existing or future ECHO chemical exposure data. We described chemical-related information collected by ECHO cohorts and reviewed ECHO-relevant literature on exposure routes, sources, and environmental and human monitoring. Fifty-six ECHO cohorts have existing or planned chemical biomonitoring data for mothers or children. Environmental phenols/parabens, phthalates, metals/metalloids, and tobacco biomarkers are each being measured by ≥15 cohorts, predominantly during pregnancy and childhood, indicating ample opportunities to study child health outcomes. Cohorts are collecting questionnaire data on multiple exposure sources and conducting environmental monitoring including air, dust, and water sample collection that could be used for exposure assessment studies. To supplement existing chemical data, we recommend biomonitoring of emerging chemicals, nontargeted analysis to identify novel chemicals, and expanded measurement of chemicals in alternative biological matrices and dust samples. ECHO’s rich data and samples represent an unprecedented opportunity to accelerate environmental chemical research to improve the health of US children.
The implementation of fuel cell vehicles requires a supervisory control strategy that manages the power distribution between the fuel cell and the energy storage device. Some of the current problems with power management strategies are: fuel efficiency optimization methods require prior knowledge of the driving cycle before they can be implemented, the impact on the fuel cell and battery life cycle are not considered and finally, there are no standardized measures to evaluate the performance of different control methods. In addition to that, the performances of different control methods for power management have not been directly compared using the same mathematical models. The proposed work will present a different optimization approach that uses fuel mass flow rate instead of fuel mass consumption as the cost function and thus, it can be done instantaneously and does not require knowledge of the driving cycle ahead of time. Also this study presents an experimental approach to validate the mathematical simulation results.
This paper introduces an innovative gamified rehabilitation platform comprising of a mobile game and a custom sensor placed on the knee, intended for patients that have undergone Total Knee Replacement surgery, in collaboration with the General Hospital in Chania. Initial testing of the system is conducted in the Hospital Orthopaedic Clinic, in collaboration with Orthopeadic Surgeons and Physiotherapists. The application uses a single custom-made, light, portable and low-cost sensor node consisting of an Inertial Measurement Unit (IMU) attached on a lower limb in order to capture its orientation in space in real-time, while the patient is completing a physiotherapy protocol. The aim is to increase patient engagement during physiotherapy by motivating the user to participate in a game. The proposed sensor node attached on the lower limb provides input to the gamified experience displayed on an Android mobile device, offering feedback to the patient in relation to whether the performed exercises were accurately conducted. A classification algorithm is proposed that automatically classifies an exercise in real-time as correct or incorrect, according to physiotherapists’ set criteria. The game projects a graphical image of the patient’s limb motion as part of a 3D computer graphics scene. It then classifies the exercise performed during physiotherapy as accurately performed or not and increases patient compliance via a reward system. Our goal is to reduce the need for the physical presence of a physiotherapist by aiding the efficient performance of exercise sessions at any location, e.g. at home, indoors and outdoors by just utilizing a light sensor and an Android device. Initial testing of the application in the Chania’s General Hospital Orthopaedic Clinic, Greece, indicates that patient engagement is enhanced in most cases, even when elderly patients are concerned.
Dolutegravir (DTG)-based antiretroviral therapy (ART) is currently the first-line treatment for people living with HIV. Neuropsychiatric adverse events (NP-AEs) have been reported with DTG but neuropsychiatric symptoms have not been systemically quantified using structured scales. This study examined mood and cognitive parameters before and after a planned transition from non-DTG to DTG-based ART within a longitudinal study of acute HIV infection (AHI).
The present study is the first to concurrently examine social cognition, neurocognition, and social functioning in psychometric schizotypes. Screening of 2108 undergraduates with the Schizotypal Personality Questionnaire–Brief (SPQ-B) identified 52 persons high in schizotypy and 40 persons low in schizotypy. All participants were administered a test battery designed to assess two elements of neurocognition, verbal secondary memory (California Verbal Learning Test) and executive functioning (Wisconsin Card Sorting Test), two elements of social cognition, emotion perception (The Awareness of Social Inference Test—Part 1) and theory of mind (The Awareness of Social Inference Test—Parts 2 and 3), and social functioning (Social Adjustment Scale–Self Report). Although the persons with high schizotypy were impaired in social functioning relative to the persons with low schizotypy, they were not impaired in theory of mind, emotion perception, verbal secondary memory, or executive functioning. Theory of mind and verbal secondary memory were correlated in persons with high schizotypy. The present findings suggest that psychometric schizotypes are not impaired in the domains of social cognition and neurocognition examined.