batterydata/paper-abstracts huggingface dataset:
State of charge (SOC) estimation is a key issue for battery management since an accurate estimation method can ensure safe operation and prevent the over-charge/discharge of a battery. Traditionally, open circuit voltage (OCV) method is utilized to estimate the stack SOC and one open flow cell is needed in each battery stack [1,2]. In this paper, an alternative method, extended Kalman filter (EKF) method, is proposed for SOC estimation for VRBs. By measuring the stack terminal voltages and applied currents, SOC can be predicted with a state estimator instead of an additional open circuit flow cell. To implement EKF estimator, an electrical model is required for battery analysis. A thermal-dependent electrical circuit model is proposed to describe the charge/discharge characteristics of the VRB. Two scenarios are tested for the robustness of the EKF. For the lab testing scenarios, the filtered stack voltage tracks the experimental data despite the model errors. For the online operation, the simulated temperature rise is observed and the maximum SOC error is within 5.5%. It is concluded that EKF method is capable of accurately predicting SOC using stack terminal voltages and applied currents in the absence of an open flow cell for OCV measurement.
Electroactive LiFePO4/C composite powders were successfully prepared by the microemulsion process under controlled conditions. A series of residual carbons on the surface of prepared LiFePO4 materials originating from the pyrolysis of various salt concentrations, Hydrophile-Lipophile-Balance (HLB) values, and structures of organic surfactants were characterized. All samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectral analysis, BET surface area, cyclic voltammetry (CV) and charge–discharge tests. The performance of the LiFePO4/C composite powders displayed a strong relationship between the emulsion conditions and structures of surfactants. Lower salt concentrations of the aqueous cores or a smaller HLB numbers cause the formation of small aqueous cores resulting in smaller particle sizes of LiFePO4/C composites after calcinating the cores. The molecular structures of surfactant affect the formation of micelle size and further influence the behavior of the LiFePO4/C composite. The OP-7 surfactant contains more branched structures on the lipophilic groups causing the formation of small aqueous cores and particle sizes of LiFePO4 after calcination of the cores. Small aqueous cores formed smaller particles with lower I D/I G values after pyrolysis yielding composites with higher discharge capacities.
This paper proposes an engineering design framework and methodology for building an energy semantic network (ESN) which helps to create and evaluate possible scenarios of energy system structure of buildings (energy generation, conversion, and conservation measures). The developed ESN does not only focus on building thermal performance (i.e. insulation materials, geometry, and dynamic behavior of building occupants) but also integrates energy resources, Hybrid Energy Supply Unit, and source-load interconnection. In other words, the developed ESN supports the design and evaluation of micro energy grid for building with various options of energy generation and conversion. Parameters identification of building energy system and their range is an important step to successfully develop energy optimization within buildings. The developed ESN generates the possible scenarios of energy generation and conversion for evaluation and optimization purposes. The structure of the ESN provides heterogeneous presentation of the classes with flexible architecture to modify, add, or delete significant energy classes. In addition, the ESN structure is designed to avoid non-realistic computational burden during simulations and evaluation. The methodology of generating the minimal possible scenarios is introduced. For validation purposes, the proposed algorithm is examined using case study of a mid-size house with different energy sources and thermal zones. The ESN of this case study is discussed, the possible scenarios of energy generation, conversion and load type are produced and their simulation and evaluation using five key performance indicators (KPIs) are introduced.
Orange juice (OJ) flavanones undergo limited absorption in the upper gastrointestinal tract and reach the colon where they are transformed by the microbiota prior to absorption. This study investigated the ability of two probiotic bacteria, Bifidobacterium longum R0175 and Lactobacillus rhamnosus subsp. Rhamnosus NCTC 10302 to catabolise OJ flavanones.
Searching for high-performance electrode materials with rapid charge/discharge and high cycling stability is pivotal to broaden the applications of lithium-ion batteries (LIBs). Herein, we report a simple nanochannel-confined synthesis technology of ultrafine Nb2O5 (<10 nm) nanoparticles encapsulated into carbon nanotubes (CNTs) hybrids for LIBs electrode materials. The three crystal forms of Nb2O5 can be respectively obtained simply by changing the temperature of thermal treatment. The ultrafine Nb2O5 nanoparticles dominated by the inner diameter of CNTs expose very high lithiation active sites. The fascinating nanostructure can also possess high structural stability with rapid electron transfer rate. Consequently, the orthorhombic Nb2O5/CNTs hybrids show a maximum specific capacity of 207 mAh g−1 at 0.1 A g−1, which can be maintained 170 mAh g−1 after 1000 cycles. More importantly, a specific capacity of 108 mAh g−1 can still be achieved even at 10 A g−1, much higher than CNTs surface loaded Nb2O5 nanoparticles hybrids. This work provides a channel-space confined synthesis insight for constructing novel electrode materials for high-rate and long-life LIBs.
The process optimization of nanocrystalline lithium manganate thin films (Li x Mn2O4; x =1.0–1.4) has been demonstrated by using a cost-effective solution growth technique. Films were first attempted with Pt–Si (Si/SiO2/TiO2/Pt) substrates but because of inter-diffusion of TiO2 buffer layer with Pt at higher annealing temperature, phase impure LiMn2O4 films were obtained. Phase pure films on the basis of XRD analysis were found on Pt substrate at specified growth parameters. The annealing temperature and annealing time were varied, the films annealed at 700°C for 2h were found to be the best films. The nanocrystalline nature of the films was revealed by the SEM micrographs and the surface morphology studied using AFM. Finally, the electrochemical properties (cyclic voltammetry and constant current measurements) of these films were analyzed using a home made three-electrode cell and Gamry Battery tester instrumentation. The formation of a prominent layer of fluoride species deposited over the cathode surface during the repeated cycling was revealed by XPS measurements. Further experiments are in progress on identifying the exact composition of these unwanted species. The formation of the Jahn-Teller active Mn3+ during electrochemical cycling was completely ruled out from the XPS analysis. Also the very consistent value of [Mn3+/Mn4+] ratio before and after electrochemical cycling on the surface of the film revealed good quality of the films. Finally, the formation of the fluoride layer was concluded as a passive layer that causes the initial capacity drop during first few cycles of the cell performance.
An in-situ and controllable redox deposition method has been applied to prepare binder-free MnO2 nanosheet array-decorated carbon paper as negative electrode for vanadium redox flow batteries (VRFB). Electrochemical performance of electrode depends on amount and uniform distribution of MnO2 on carbon paper, which were controlled by solution pH, KMnO4 concentration, and deposition time. Modified carbon paper (CPA-05-30) with a uniform MnO2 nanosheet coating layer was obtained in 0.05 M KMnO4 + 0.5 M H2SO4 solution for 30 min. CPA-05-30 presents the most excellent electrocatalytic performance for V3+/V2+ redox reaction. On CPA-05-30, charge transfer and diffusion processes for V3+/V2+ redox reaction are accelerated as a result of MnO2 nanosheet with high catalytic activity and excellent hydrophilcity. Therefore, loading MnO2 on carbon paper improves electrochemical activity V3+/V2+ redox reaction. Moreover, in charge-discharge test, the cell using CPA-05-30 as negative electrode shows higher discharge capacity and better capacity retention at 50 mA cm−2 for 50 cycles in comparison with pristine cell. It indicates that MnO2 nanosheet can efficiently increase electrolyte utilization. At 100 mA cm−2, energy efficiency of the cell using CPA-05-30 is 66.4%, which is 6.0% higher than that of pristine cell. MnO2 nanosheet decorated carbon paper shows excellent electrochemical properties for energy storage application, which evidences its potential application in VRFB.
The compounds Na3M2(PO4)2F3 [M = Ti, Fe, V] were obtained by two-step solid-state synthesis, and its electrochemical properties as cathode active materials of sodium-ion batteries were investigated. The obtained Na3M2(PO4)2F3 materials were found to have a tetragonal structure with a space group, P4 2 /mnm, and were isostructural with β-Na3V2(PO4)2F3 by X-ray powder diffraction (XRD) measurements. Within this series, Na3V2(PO4)2F3 in particular exhibited stability on cycling and a capacity of approximately 120 mAh g−1 against sodium metal. Capacity retention for this compound was 98%, even after the 40th cycle of prolonged charge/discharge measurements. Ex-situ XRD data for Na3V2(PO4)2F3 electrodes charged and discharged at selected voltages showed that the material structure expanded along the c axis during charging up to 4.3 V and returned to its original dimensions after cycling. This is attributed to the extraction/insertion of Na atoms layers along the (002) a–b plane in the tetragonal structure.
Publisher Summary Ethical engineering is socially responsible engineering. Green engineering is also a bioethical tenet wherein environmentally conscious attitudes, values, and principles, combined with science, technology, and engineering practice, all directed toward improving local and global environmental quality. Green has become recognized as a code for sustainable programs. The term green engineer is no longer a neophyte to the profession, it is now more likely to mean an environmentally oriented engineer. One of the principles of green engineering is the recognition of the importance of sustainability. The underlying purpose of sustainable development is to help developing nations manage their resources, such as rain forests, without depleting these resources and making them unusable for future generations. In short, the objective is to prevent the collapse of the global ecosystems. Therefore, sustainability is a systematic phenomenon, so it is not surprising that engineers have embraced the concept of sustainable design. At the largest scale, manufacturing, transportation, commerce, and other human activities that promote high consumption and wastefulness of finite resources cannot be sustained. At the individual designer scale, the products and the processes that engineers design must be considered for their entire lifetime and beyond.
We use the comet assay as part of our genotoxicity screening battery for newly synthesized drug candidates. A dataset of more than 250 tests carried out with 75 drug candidates of various chemical classes was analyzed to elucidate the influence of cytotoxicity and compound precipitation on DNA migration in the comet assay. Using a V79 Chinese hamster cell line, 38 of the compounds were negative and 37 were positive in the comet assay. The reproducibility of test results between repeat experiments was 85%. Data on 72 tests with a negative call in which the compounds were tested up to highly cytotoxic concentrations demonstrated that cytotoxicity, as determined by Trypan blue dye exclusion and occurrence of cells with completely fragmented chromatin, did not lead to false positive test results. The majority (64.2%) of compounds with a positive call induced elevated DNA migration in the absence of excessive cytotoxicity. Compound precipitation was observed in 84 tests. In 88.1% of these cases, the test result at the precipitating concentration did not differ from that found at the highest soluble concentration. Half of the remaining 11.9% of contrary results (most of them weak effects) were not reproducible in the respective repeat experiment, indicating no or only a negligible influence of precipitation on test results. The data indicate that using V79 cells, the comet assay specifically detects genotoxic effects and is not confounded by cytotoxicity or compound precipitation under the conditions used.
Highly electrocatalytic activity and strong stability towards both oxygen evolution (OER) and oxygen reduction reaction (ORR) have been regarded as the critical factors in widespread application for the renewable energy technologies. It still remains a huge challenge for developing bifunctional catalysts with low cost, efficiently electrocatalytic activity and strong stability. In this paper, FeCo alloy nanoparticles embedded in nitrogen-doped carbon are synthesized through a simple thermal decomposition of Co-Fe Prussian Blue Analogue (Co-Fe PBA) in Ar atmosphere, during which the organic ligand of CN− in Co-Fe PBA provides both carbon and nitrogen sources for forming nitrogen-doped carbon and FeCo alloy nanoparticles were formed, and thus producing a core-shell structure (FeCo@NC). According to a set of electrochemical tests, the obtained FeCo@NC can function as a Janus to drive OER and ORR with desirable activities and stabilities in alkaline media. Specifically, the FeCo@NC presents an onset-potential of 1.45V, a potential of 1.49V at 10mAcm−2, a Tafel slope of 62mVdec−1 as OER catalyst, and an onset potential of 0.94V, a half-wave potential of 0.8V as ORR catalyst. The performance is comparable to those of precious metal based electrocatalysts, making it possible for potential application in the renewable energy devices, especially Zn-air battery.
In order to develop high energy density Li rechargeable batteries, nano-sized materials have attracted attention as the active materials. Mesoporous materials consist of the micrometre-sized particles, and they have high surface area due to their mesopore and thin wall thickness of framework. Here, we synthesize a highly ordered mesoporous RuO2 to investigate the effect that the mesoscopic structure has on the capacity and their corresponding reaction mechanism of Li rechargeable battery. The synthesized mesoporous RuO2 shows an initial discharge capacity of 1366 mAh g−1 on mesoporous RuO2, which is higher than that of commercial RuO2. Our findings via In situ X-ray analysis techniques combined with electrochemical analysis demonstrate that the additional capacity of mesoporous RuO2 is resulted from the enhanced interfacial reaction between Ru metal and Li2O formed by conversion reaction of RuO2. Nano-size effects of mesoporous structure such as high surface area, easy electron transport, and small domain would enable to improve the interfacial reaction of highly ordered mesoporous RuO2. The understanding of this relationship between structural engineering and electrochemical properties provides the insight into development of high energy density anode materials in next generation Li rechargeable battery.
While evidence-based treatments exist for posttraumatic stress disorder (PTSD), a significant sub-set of veterans continue to meet criteria for PTSD after treatment. Sleep problems may affect treatment retention and predict efficacy for PTSD treatments. The present study used data from a clinical trial of Prolonged Exposure therapy (PE) administered to veterans (N=154) to evaluate whether residual sleep symptoms remained after treatment completion, and if so, whether these residual sleep symptoms were associated with higher levels of PTSD and comorbid depression at the end of treatment. Participants (ages 20 to 75 years old; 35.7% Black; 54.5% married) completed demographic questions, symptom assessments, and engagement-related surveys. Hierarchical multiple linear regression models demonstrated that changes in sleep were significant predictors of PTSD and depression symptom reduction above and beyond the influence of demographic and engagement factors (e.g., therapy satisfaction). Greater residual sleep symptoms were predictive of smaller treatment gains. Findings illustrate the potential significance of sleep during the course of PTSD treatment, leading to several important clinical assessment and treatment implications.
Patients with conduction aphasia have been characterized as having a short-term memory deficit that leads to relative difficulty on span and repetition tasks. It has also been observed that these same patients often get the gist of what is said to them, even if they are unable to repeat the information verbatim. To study this phenomenon experimentally, patients with conduction aphasia and left hemisphere-injured controls were tested on a repetition recognition task that required them to listen to a sentence and immediately point to one of three sentences that matched it. On some trials, the distractor sentences contained substituted words that were semantically-related to the target, and on other trials, the distractor sentences contained semantically-distinct words. Patients with conduction aphasia and controls performed well on the latter condition, when distractors were semantically-distinct. However, when the distractor sentences were semantically-related, the patients with conduction aphasia were impaired at identifying the target sentence, suggesting that these patients could not rely on the verbatim trace. To further understand these results, we also tested elderly controls on the same task, except that a delay was introduced between study and test. Like the patients with conduction aphasia, the elderly controls were worse at identifying target sentences when there were semantically-related distractors. Taken together, these results suggest that patients with conduction aphasia rely on non-phonologic cues, such as lexical-semantics, to support their short-term memory, just as normal participants must do in long-term memory tasks when the phonological trace is no longer present.
Many 21st century technological solutions are reliant on the development of new materials with improved properties, and increasingly on materials that can be optimised to perform more than one function. High-throughput and combinatorial methodologies are being used more frequently to discover and design improved materials in a time efficient manner for a variety of applications. A number of technological challenges involve the field of electrochemistry, such as battery development, electrocatalysis, photocatalysis, corrosion protection, sensor development, photovoltaics and light-emitting materials. This review focuses on the utilisation of high-throughput and combinatorial methods that have incorporated, or are associated with, electrochemical methods. In many cases electrochemical determinations are well-suited for high-throughput methodologies, enabling direct quantitative analysis of properties. However, in other circumstances electrochemical measurements are complicated by additional factors. Hence the limitations of high-throughput and combinatorial electrochemistry are also discussed within.
The Li–S battery is with a much greater theoretical energy density than those of conventional lithium ion batteries. The key to achieve a high performance electrode for Li–S battery lies in the arrangement of the building blocks into a well-designed structure, in which the nanocarbon framework not only acts as an electronic conduit to the encapsulated active materials but also serves as a mini-electrochemical reaction chamber. Therefore, a nanocomposite with sulfur entrapped into hierarchical porous graphene was proposed and fabricated for Li–S batteries. The nanocomposite electrode exhibits high discharging capacitance of 1068 and 543mAhg−1 at a current density of 0.5 and 10C, respectively. The discharging capacity of 386mAhg−1 can be presented at ultra-low temperature of −40°C, which far exceeds the operating range of conventional lithium-ion batteries. The large scale produced hierarchal graphene was mainly decorated with epoxy and hydroxyl groups, which can enhance the binding of S to the C–C bonds due to the induced ripples by the functional groups. These results provided a promising electrode material for energy storage device with high capacitance, which is important for the increasing demands of power sources in cold environments, such as battery systems for electric vehicles in cold zone or for aeronautic applications.
The electrochemical performance and electrode reaction using Au–Pd nanoparticle (NP) supported mesoporous β-MnO2 as a cathode catalyst for rechargeable Lithium-Air (Li-Air) battery is reported here for the first time. In this study, Au–Pd NP-supported mesoporous β-MnO2 was successfully synthesized by hydrothermal process using a silica KIT-6 template. It has an initial discharge capacity of ca. 775 mAh g−1 with high reversible capacity at a current density of 0.13 mA cm−2. The Au–Pd NP-supported mesoporous β-MnO2 cathode catalyst, which enhances the kinetic of oxygen reduction and evolution reactions (ORR/OERs), thereby improves energy and coulombic efficiency of the Li-Air cell. Raman spectroscopy and ex-situ XRD results of the Au–Pd NP-supported mesoporous β-MnO2 air electrode suggest that the observed capacity comes from oxidation of Li+ to form Li2O2 during discharge to 2.0 V.
The layered structure LiNi1/3Co1/3Mn1/3O2 cathode material was successfully prepared via a carbonate co-precipitation method, followed by a calcination process at high temperature. The effects of precipitant agent on the crystal structure and morphology of the prepared materials have been studied by XRD, SEM, and the electrochemical performance was investigated by galvanostatic charge–discharge test, cyclic voltammetry and electrochemical impedance spectroscopy. The carbonate precursors (Ni1/3Co1/3Mn1/3)CO3 synthesized by different precipitant agent show a single phase of hexagonal carbonate but a great difference in morphology. The well-crystallized product LiNi1/3Co1/3Mn1/3O2 with homogeneous mixing of transition metal ions were obtained via different precipitants. The material made form Na2CO3 +NH4HCO3 precipitant shows the smallest particles size without agglomeration, the lowest polarization and the lowest interfacial resistance, which leads to excellent comprehensive electrochemical performance.