batterydata/paper-abstracts huggingface dataset:
A cross-linked polyurethane acrylate (PUA) is synthesized by end-capping a hexamethylene diisocyanate, hexamethylene diisocyanate/poly(ethylene glycol)-based prepolymer with hydroxy butyl methacrylate (HBMA). Significant interactions of lithium ions with the soft and hard segments of the host polymer are observed for the PUA complexed with lithium perchlorate (LiClO4) by means of differential scanning calorimetry (DSC), and Fourier transform infra-red (FT-IR) spectroscopy measurements. The DSC results indicate the formation of transient cross-links with the ether oxygen of the soft segment and mixing of soft and hard phases induced by the Li+ ions. The results of FT-IR spectroscopy and thermogravimetric analysis measurements support the formation of different types of complexes by interaction of Li+ ions with different coordination sites of PUA. No detectable interactions are found between Li+ ions and groups in HBMA. In addition, PUA follows the Arrhenius relationship for ion transport. Predominant formation of contact ion-pairs of LiClO4 is observed through a.c. conductivity and DSC measurements. The lithium stripping–plating process is reversible and this implies better electrochemical stability over the working voltage range. Also, the PUA electrolyte shows better compatibility with lithium metal as inferred from impedance measurements and has a good cationic transference number that is suitable for the material to be used as a solid polymer electrolyte. Addition of HBMA into the PU matrix improves the tensile strength of the cross-linked PUA. Swelling measurements of PUA with plasticizer indicate better dimensional stability. A cell is constructed with PUA as the electrolyte and its performance is evaluated.
The application of lithium ion batteries in plug-in hybrid electric vehicles (PHEVs) requires safety, high energy density, high power density, excellent cyclability and good low temperature performance. On the basis of thermally stable Li3V2(PO4)3/C and cost-effective performance carbon additives, we designed a Li3V1.97Zn0.05(PO4)3/(C+10PB) (PB stands for performance carbon additives PBX101) cathode that meets the above requirements for PHEVs battery. Firstly, its Ragone plot presents an excellent energy density retention at high power rates; secondly, the excellent capacity retention and high Coulombic efficiency of Li3V1.97Zn0.05(PO4)3/(C+10PB)-Li half-cell clearly indicates a potential good cyclability of full cells based on Li3V1.97Zn0.05(PO4)3/(C+10PB) cathode. Finally, we believe the good low temperature performance of Li3V1.97Zn0.05(PO4)3/(C+10PB) (i.e. retains 91.6% and 76.3% of its capacity at ∼25°C, when cycled at 0 and -15°C) is also beneficial to its application in PHEVs.
Li2Ti3O7 is considered to be a promising insertion material for high power battery applications because of its open structure with accessible vacancies. High-rate cycling (C/10 and 1.5C) has been performed and results show small irreversibility and low polarisation, but capacity losses are noticed during cycling. Partly substituting TiIV with FeIII improves the cyclability but a significant irreversible part is obtained due to the participation of iron in the insertion mechanism. This additional reduction level lowers with a combination of two transition elements, Fe and Ni, on the ramsdellite framework sites. Moreover, lower polarisation and higher capacities are observed. In this work, TiIV and Li are partly replaced by a combination of three elements (FeIII, NiII and AlIII) in order to further improve the electrochemical performances. The difference in charge balance is obtained by metal and oxygen vacancies, which implies new vacancies and a better accessibility to the existing vacancies for lithium insertion. Several characterisation methods have been used on three different samples (Fe, Fe/Ni and Fe/Ni/Al), which made it possible to observe wider channels in the distorted ramsdellite lattice. In this case, lithium ions circulate more easily into the channels resulting in better reversibility upon cycling, which is necessary for high-rate cycling.
Objective To compare the histopathological structure and immunohistochemical characteristics of acquired cholesteatoma in children and adults. Study design Prospective clinical study in a tertiary care centers. Material & methods This study was conducted on 40 patients presenting with cholesteatomatous middle ear disease. Twenty patients were of a pediatric age group (<18years) and the rest were adults (>18years). Patients were admitted to either the ENT Department of Alexandria University Hospital or that of the Students’ Hospital. All cholesteatoma specimens were collected intra-operatively and preserved for histopathological examination and immunohistochemical technique (PCNA monoclonal antibody). Results Histopathological examination of the submitted specimens revealed that strips of stratified squamous epithelium with the underlying tissues were fibrous in adults while cellular inflammatory infiltrates were seen in children. The degree of fibrosis was significantly higher in the adult group. Immunohistochemical examination revealed significantly higher expression scores of the proliferation marker in the pediatric group. In the matrix: The mean of PCNA/LI of adult squamous epithelium was 17.75±12.08 and of children’s cases was 32.82±17.09. In the perimatrix: The mean of PCNA/LI of adult inflammatory infiltrate was 14.77±17.28 and in children was 24.22±22.61. The differences of both were statistically significant. Conclusion The degree of fibrosis was significantly higher in adult specimens indicating a reparative process and less invasiveness. PCNA expression was significantly higher in the matrix and perimatrix of pediatric cholesteatoma as correlated to its increased proliferation. Pediatric cholesteatoma was more aggressive and invasive than adult cholesteatoma.
Cycle life studies have been done on lithium-ion pouch cell with LiCoO2 as cathode and meso-carbon micro-beads (MCMB) as anode at five different temperatures. By using the rate capability tests done at the same temperature as that of cycling and the half cell studies done on the fresh and cycled individual electrodes, the stoichiometric windows of individual electrodes at the beginning and at the end of cycling have been estimated. By analyzing these estimates along with the X-ray diffraction studies and half cell studies on cycled cathodes, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and half cell studies on cycled anodes, possible causes of increased capacity fade with increasing temperature were found to be the anode active material loss, probably due to a solvent/salt reduction reaction on the anode. Lithium deposition on the anode also has been identified as a possible side reaction during later stages of cycling at 35 and 45°C.
ABSTRACT Background This article reviews the historical development of informed consent law and highlights factors dentists must consider when deciding how to obtain valid informed consent from patients. Conclusions Informed consent laws vary from state to state. Dentists should review the laws in their states to determine when they are legally required to obtain informed consent, what information must be disclosed for the consent to be valid and how to secure consent for minor patients and adult patients who are not legally competent. Practice Implications Dentists should ensure that they are familiar with and in compliance with the informed consent laws in their states. ADA-member dentists also should be mindful of their ethical obligation to inform patients of proposed treatment and reasonable alternatives.
This study assessed the combination of two microswitches with a voice output communication aid (VOCA) with two persons (an adolescent and a young adult) with multiple disabilities. The microswitches allowed the participants to obtain direct access to preferred environmental stimuli; the VOCA enabled them to ask for caregiver's attention. Initially, the participants were taught to use each of the two microswitches individually and then together. Next, they were taught to use the VOCA and, eventually, this was available together with the microswitches. Results showed that the participants learned to operate the microswitches and the VOCA and used all three of them consistently when they were simultaneously available. Implications of these findings and the potential role of a VOCA combined with conventional microswitches were discussed.
The rehabilitation of French former uranium mining sites has not prevented the contamination of the surrounding aquatic ecosystems with metal elements. This study assesses the impact of the discharge of treated uranium mining effluents on periphytic diatom communities to evaluate their potential of bioindication. A 7-month survey was conducted on the Ritord watercourse to measure the environmental conditions of microalgae, the non-taxonomic attributes of periphyton (photosynthesis and biomass) and to determine the specific composition of diatom assemblages grown on artificial substrates. The environmental conditions were altered by the mine waters, that contaminate the watercourse with uranium and with chemicals used in the pit-water treatment plants (BaCl2 and Al2(SO4)3). The biomass and photosynthetic activity of periphyton seemed not to respond to the stress induced by the treated mining effluents whereas the altered environmental conditions clearly impacted the composition of diatom communities. Downstream the discharges, the communities tended to be characterized by indicator species belonging to the genera Fragilaria, Eunotia and Brachysira and were highly similar to assemblages at acid mine drainage sites. The species Eunotia pectinalis var. undulata, Psammothidium rechtensis, Gomphonema lagenula and Pinnularia major were found to be sensitive to uranium effluents whereas Neidium alpinum and several species of Gomphonema tolerated this contamination. The relevance of diatoms as ecological indicator was illustrated through the changes in structure of communities induced by the discharge of uranium mining effluents and creates prospects for development of a bioindicator tool for this kind of impairment of water quality.
The EU directive on waste of electrical and electronic equipment (WEEE) 2002/96/EC has set a goal of recovering 70–80% in terms of materials and energy. Nowadays, thermal cracking (pyrolysis) of such waste streams is receiving renewed attention, due to the energy and material recovery that can be achieved and therefore the sustainable waste management. However, it still lacks the kinetic background which is of great importance for a successful design of thermochemical processes. In this study the kinetic parameters of WEEE (originating from small household appliances) pyrolysis using highly pre-heated nitrogen under six different heating rates (1–2.5K/s) have been estimated using a combination of model-free and model fitted methods. Even though WEEE is heterogeneous material, similar behavior at each of the six different heating rates applied was observed. The activation energy of the pyrolysis process determined with two different model-free methods gave comparable results. Pre-exponential factor and reaction order were determined using the Coats-Redfern method. The estimated kinetic parameters for the WEEE pyrolysis are: E =95.54kJ/mol, A =1.06×108 and n =3.38.
Gel polymer electrolytes were prepared by immersing a porous poly(vinylidene fluoride-co-hexafluoropropylene) membrane in an electrolyte solution containing small amounts of organic additive. Three kinds of organic compounds, thiophene, 3,4-ethylenedioxythiophene and biphenyl, were used as a polymerizable monomeric additive. The organic additives were found to be electrochemically oxidized to form conductive polymer films on the electrode at high potential. By using the gel polymer electrolytes containing different organic additive, lithium metal polymer cells, composed of lithium anode and LiCoO2 cathode, were assembled and their cycling performance evaluated. Adding small amounts of a suitable polymerizable additive to the gel polymer electrolyte was found to reduce the interfacial resistance in the cell during cycling, and it thus exhibited less capacity fade and better high rate performance. Differential scanning calorimetric studies showed that the thermal stability of the fully charged LiCoO2 cathode was improved in the cell containing an organic additive.
The WHODAS-2 is a disability assessment instrument based on the conceptual framework of the International Classification of Functioning, Disability, and Health (ICF). It provides a global measure of disability and 7 domain-specific scores. The aim of this study was to assess WHODAS-2 conceptual model and metric properties in a set of chronic and prevalent clinical conditions accounting for a wide scope of disability in Europe.
The graphene oxide/polyaniline (GO/PANI) composite was prepared by the one-step electrochemical co-deposition method. The different mass concentrations of GO were utilized to improve the electrochemical performances. Scanning electron microscope and transmission electron microscope images showed that PANI nanofibers not only were coated on the surface but also intercalated into GO sheets. The maximum specific capacitance of the GO/PANI composite achieved 1136.4Fg−1 with a GO concentration of 10mgL−1 at a scan rate of 1mVs−1, which is almost two-fold higher than that of PANI (484.5Fg−1). The GO/PANI composite also showed a good cycling stability, retaining over 89% of its initial capacitance after 1000 cycles. High electrochemical performances were attributed to increasing active sites for the deposition of PANI provided by large surface areas of GO sheets and the synergistic effect between GO and PANI, shortening the ion diffusion paths. Results indicate that the GO/PANI composites can be developed as excellent electrode materials of high-performance supercapacitor by a versatile, effective and environment-friendly method.
Abstract Since the 1970s, there has been increased massive development in the transportation sector, accelerating the construction of roads, bridges, tunnels, and hardscapes that are eventually causing deadly environmental crisis. We certainly need advanced technology for the infrastructure and transportation sector to mitigate the environmental crisis. Therefore in this chapter, a sustainable infrastructure and high-tech transportation system has been proposed by implementing all possible advanced engineering applications to confirm an environmentally friendly infrastructure and faster, cleaner, and safer transportation system to develop a resilient urban and rural area.
The electrochemical properties of LiNi0.6Co0.2Mn0.2O2, such as cycling stability, rate capacity and coulomb efficiency, are not fairly well at large rate, high cutoff voltage and elevated temperature. In this article, a uniform nanoscale graphene@TiO2 coating layer is skillfully formed on the surface of LiNi0.6Co0.2Mn0.2O2 via an artful sol-gel-based method. The rGO@TiO2 layer is evidenced by a series of detections, and the structures of the pristine and coated materials are investigated in detail. It indicates that the graphene@TiO2 layer with a thickness of ∼2 nm is uniformly covered on the LiNi0.6Co0.2Mn0.2O2 particles. The “synergistic effects” of graphene@TiO2 composite plays an important role in improving the comprehensive electrochemical performances of the cathode material. Compared with the pristine material, the graphene@TiO2 co-modified LiNi0.6Co0.2Mn0.2O2 shows enhanced electrochemical performances at large rate, elevated temperature, and high cutoff voltage. Particularly, it displays capacity retentions of 93.7% and 89.2% after 150 cycles at 1 C and 2 C, respectively, over 3.0–4.5 V. Even at high temperature of 55 °C and upper operating voltage of 4.5 V, the capacity retention of graphene@TiO2-coated sample increases almost 50% compared with the pristine sample after 150 cycles.
In the manufacturing of Li-ion battery cells, filling with electrolyte liquid is a crucial step in terms of product quality and cost. To gain insight into the process phenomena, a non-destructive imaging method is presented. It is shown that the spreading of electrolyte liquid within the cell during filling and wetting can be visualized by neutron radiography. The experiment allows for the first time to visualize the soaking behaviour of electrolyte liquid in battery cells. The influence of the process parameters on the wetting behaviour is studied and flow paths of the liquid are identified. The electrolyte intake into the cell stack is discussed with two different analytical approaches. Based on the experimental data, the production process can be optimized, leading to stable cell performance and cost reduction due to faster processes and lower scrap rates.
Nickel phosphide (Ni3P) is a promising anode material for lithium-ion batteries owing to its high specific capacity, though significant improvement in its cycling stability is highly desired. Here we propose an effective and low-cost solution via a three-dimensional construction of porous NiO covered Ni3P films over a substrate of Ni foam, through electroless plating of P-rich Ni3P and subsequent in situ oxidation in air. The in situ oxidation of P-rich Ni3P resulted in the formation of nano porous NiO capping layer. Remarkable enhancement in the cycling stability of such a composite anode was thus realized. The initial discharge capacity for a CR2016-type coin cell was as high as 920 mAhg−1, and there was still a reversible capacity of 550 mAhg−1 after 60 cycles at a current density of 38.8mAg−1. The presence of porous NiO capping layer changed the lithiation path and significantly improved the cycling performance. The decreased resistance in charge transport due to the existence of adequate channels for Li ions diffusion also enhanced rate performance. A pristine Ni3P films was researched as a comparison.
Sensing coverage and network connectivity are two of the most fundamental problems in wireless sensor networks. Finding an optimal node deployment strategy that would minimize cost, reduce computation and communication overhead, be resilient to node failures, and provide a high degree of coverage with network connectivity is extremely challenging. Coverage and connectivity together can be treated as a measure of quality of service in a sensor network; it tells us how well each point in the region is covered and how accurate is the information gathered by the nodes. Therefore, maximizing coverage as well as maintaining network connectivity using the resource constrained nodes is a non-trivial problem. In this survey article, we present and compare several state-of-the-art algorithms and techniques that aim to address this coverage–connectivity issue.
Na4Fe3(PO4)2P2O7 (NFPP) was synthesized by the fast and facile mechanochemically assisted solid-state route using iron oxalate as a precursor. By means of XRD, FTIR, and Mӧssbauer spectroscopy, it was found that NFPP prepared by annealing the activated mixture at 450 °C is the most homogeneous phase and shows the best electrochemical behavior when cycling in both Na and Li cells. During its cycling in a Li cell and chemical treatment with LiBr the Na+/Li+ ion exchange occurs. It has been shown that in both cases the process is not fully complete and leads to the formation of the mixed Na/Li compounds. Phase composition, crystal and local structure, and electrochemistry of the as-prepared mixed Na/Li iron ortho-pyrophosphates were investigated. We concluded that the remaining Na+ ions stabilize the structure of Na4-xLixFe3(PO4)2P2O7 (NLFPP) during cycling, and the simultaneous Na+/Li+ (de)intercalation at the cathode side is realized in the hybrid Na/Li cells. Mixed NLFPP can be considered as promising cathode materials for Li-ion batteries with high energy and power characteristics.
Published accounts of abuse testing of lithium-ion cells and components are summarized, including modeling work. From this summary, a set of exothermic reactions is selected with corresponding estimates of heats of reaction. Using this set of reactions, along with estimated kinetic parameters and designs for high-rate batteries, models for the abuse behavior (oven, short-circuit, overcharge, nail, crush) are developed. Finally, the models are used to determine that fluorinated binder plays a relatively unimportant role in thermal runaway.
Li2Zn0.93Mo0.07Ti3O8@graphene conductive network is successfully synthesized via a simple solid-state reaction. The designed structure is highly advantageous to its electrochemical performance. After cycling for 600 cycles, 82.4% of the capacity for the 2nd cycle is kept at 1 A g−1. After 300 cycles, 210 and 179 mAh g−1 are obtained at 2 and 3 A g−1, respectively. Even at the high current densities of 4 and 5 A g−1, 164 and 153 mAh g−1 are still delivered at the 200th cycle, respectively. In addition, the Li2Zn0.93Mo0.07Ti3O8@graphene has good cyclic performance at the high temperature of 55 °C. The excellent cyclic performance and the large specific capacities at high rate are due to the good conductive network, stable structure, large pore volume, small particle size, and good kinetics behavior.
A thermal modeling was performed to study the effect of the electrode configuration on the thermal behavior of a lithium-polymer battery. It was examined the effect of the configuration of the electrodes such as the aspect ratio of the electrodes and the placing of current collecting tabs as well as the discharge rates on the thermal behavior of the battery. The potential and current density distribution on the electrodes of a lithium-polymer battery were predicted as a function of discharge time by using the finite element method. Then, based on the results of the modeling of potential and current density distributions, the temperature distributions of the lithium-polymer battery were calculated. The temperature distributions from the modeling were in good agreement with those from the experimental measurement for the batteries with three different types of electrodes at the discharge rates of 1C, 3C, and 5C.
Traditional electrochemical algorithms are too complex for use in real-time battery management systems (BMSs). Determination of parameters and implementation of algorithms are the key challenges for electrochemical models for Li-ion batteries. This paper develops a simplified electrochemical model that incorporates open-circuit voltage, liquid-phase diffusion, reaction polarization, and ohmic polarization, and uses a fast operating test to identify all the parameters to solve these challenges. The model is then implemented and compared against experimental measurements. Validations of parameter estimation and charge/discharge behaviors indicate that the developed parameter estimation method for the electrochemical model is effective. With this model and parameter estimation technique, electrochemical model-based state of charge (SOC) estimation can be realized online and can provide accurate results.
The mechanisms for binder delamination from electrode particles in porous lithium-ion electrodes are considered. The problem is analysed using a model that makes use of a multiscale continuum description of the battery electrode and specifically accounts for the viscoelastic properties of the binder [9]. This model predicts the evolution of the stress fields in the binder in response to: (i) binder swelling due to electrolyte absorption during cell assembly, and; (ii) shrinkage and growth of the electrode particles during cell cycling. The model predictions provide a cogent explanation for morphological damage seen in microscopy images of real cathodes. The effects of altering electrode particle shape, binder rheology and cycling rates on binder delamination are all investigated and used to make suggestions on how electrode lifetimes could be extended.