batterydata/paper-abstracts huggingface dataset:
In this paper, an analysis of the performance, failure and reliability, as well as a spare parts analysis have been conducted for a wind farm, which has 15 wind turbine generators (WTGs), each of 225 kW capacity. This wind farm is located at Muppandal, Tamil Nadu, South India. The average value of performance parameters such as technical availability, real availability and capacity factor for the wind farm were 94%, 82.88% and 24.9% respectively during the years 2000–2004. This paper also deals with Pareto analysis to find out the reduction in problems, when one problem is tackled partly and completely. The Weibull technique was also used for the reliability analysis. The reliability factor in the initial period after one year seems to be good as the wind farm has a lower failure rate of 0.000019. As a supplemental activity, spare parts optimization was also carried out for a few vital components of this wind farm and the results are presented. The failure and its financial implications are also analyzed in this paper.
Graphite anode behaviour is of great interest for the optimization of Lithium-ion batteries. The improvement of battery performance depends on an understanding of lithium intercalation/de-intercalation in graphite anodes, especially in regards to energy and power density. In this study we present a new approach for investigating graphite anode behaviour under equilbirum and nonequlibirum conditions. It is based on reflectance change measurements from a graphite anode surface, relative to state of charge (SOC). We have introduced an innovative optical test cell and used a photodiode. A reflectance change hysteresis occurs between lithium intercalation and de-intercalation, under equilbrium conditions. This was ascribed to specific lithium-carbon bonds at the graphite particle edge region. Charging and discharging have a unique reflectance change characteristic. This was assigned to SOC nonequilibrium in the anode and serves as clear evidence that limited lithium mobility in the porous microstructure is a signficant loss factor. We then performed a more detailed analysis of the anode loss processes by correlating the anode reflectance change with dynamic electrical excitation. This method, Optical Impedance Spectroscopy (OIS), provided detailed information about the frequency range of the loss processes. It also confirmed our assigning the low frequency range (1mHz-3Hz) to solid state diffusion and lithium transport in the electrolyte filled pores. The results are in excellent agreement with previous EIS studies. We conclude that OIS is applicable for validating physicaly-based graphite anode models and determining model parameters, in combination with EIS.
The carbon-coated Si nanoparticle/graphene composite (Si@C/G) was prepared through a thermal annealing of the freeze-dried mixture of Si nanoparticles, sucrose, and graphene oxide. This straightforward approach realizes the carbon coating of Si nanoparticles and the good dispersion of graphene sheets in Si@C nanoparticles simultaneously. As an anode material for lithium-ion batteries, the Si@C/G exhibits high Coulombic efficiency, good cycling stability of 1410 mAh g−1 at a current density of 500mAg−1 after 100 cycles, and superior rate capability. Such excellent electrochemical performance could be attributed to the combined work of carbon shells and electrically conductive graphene networks. This study proposes a strategy for other electrode materials with huge volume changes and low electrical conductivity to improve the lithium storage performance.
A simple capacitor is perceived as being capable of discharge (or recharge) at high rates, limited only by a small equivalent series resistance. However, in the case of electrochemical capacitors, based on high specific area porous electrode materials, power limitations arise due to the complex-distribution of electrolyte internal resistance, coupled with double-layer or pseudo-capacitative elements. The present paper quantitatively examines both numerically and experimentally the effects of internal electrolyte resistance as evaluated by the current-response functions for porous capacitor electrodes, generated in cyclic voltammetry (CV) experiments and for voltage versus time responses in dc charge/discharge regimes.
Drug-induced liver injury (DILI) is a major contributor to attrition within drug development, causing a significant patient morbidity and mortality. Prediction of clinical DILI from in vitro and in vivo data remains difficult. Currently utilized hepatic injury biomarkers often lack sensitivity and specificity to indicate that a patient is progressing toward overt DILI; thus, new biomarkers are needed. Currently, ‘Hy's law’, reflecting ALT and bilirubin increases, represents the gold standard model to predict serious DILI and the standard for novel DILI biomarkers to surpass. Pre-clinical and clinical studies have shown the utility of biomarkers such as cytokeratin-18, high mobility group box-1, glutamate dehydrogenase, microRNA-122 and HLA-associated genotypes as sensitive and translational biomarkers of DILI. Qualification of these biomarkers requires additional data, including inter- and intra-subject variability, impact of gender, age, and diurnal variation in healthy volunteers. Additionally, the utility of these biomarkers to identify idiosyncratic DILI and the prediction of serious DILI from benign elevations in ALT activity remain to be assessed. These challenges are the current focus of the Predictive Safety Testing Consortium (PSTC) in the US and the IMI Safer and Faster Evidence based Translation (SAFE-T) consortium in Europe. However, in the near future, these proposed biomarkers are likely to retain their exploratory status as formal biomarker qualification is lengthy and challenging. A more intelligent use of currently used markers, such as ALT activity, in the meantime can bridge the gap between novel biomarkers being used in the experimental context to formal qualification. The current status of novel DILI safety biomarkers with clinical potential and their use alongside established markers will be discussed in the context of advancing fundamental mechanistic drug safety science.
Accurate battery models are essential for the assessment of battery states and performance. Traditional equivalent circuit model (ECM), e.g. second-order RC model, cannot imitate non-linear characters of Lithium-ion battery especially in low state of charge (SOC) area. Considering the advantages of battery electrochemical and ECM, the paper proposes an electrochemistry-based equivalent circuit model (E-ECM). With only two parameters more than second-order RC model, E-ECM can simulate battery voltage response better. Next, different from the previous model parameters optimization method, a decoupling parameters extraction (DPE) method is studied to derive the more appropriate model parameters for the proposed E-ECM first. The DPE method is believed to relate to battery electrochemical characters. Experiment results show that the obtained E-ECM is of a good performance no matter in the dynamic working conditions, or constant current working condition, especially in low SOC area. Moreover, the proposed E-ECM is able to describe battery rate capability with high accuracy.
While Li–S batteries are poised to be the next generation high-density energy storage devices, the low sulfur utilization and intrinsic polysulfide shuttle have limited their practical applications. Here, we report that radical polymer Poly(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl methacrylate) (PTMA)—a stable free radical polymer reported to be potential organic electrode materials–can perform as a multifunctional sulfur-trapping and catalytic binder for high performance Li-S batteries once activated via in-situ electrochemical oxidation. The activated PTMA+ not only displays strong binding affinity to polysulfides but also provides PTMA+-assisted additional redox sites and improves the kinetics of the cathode reaction. Thus the novel multifunctional additive for Li-S batteries results in improved cycle life, faster rate performance and most importantly, a significantly increase in specific discharge capacity by ~80%, with specific capacity of 1254mAh/g and Coulombic efficiency of 96% at a four-hour charge/discharge (C/4) current rate.
The intercalation and deintercalation mechanisms of lithium into V2O5 thin films prepared by thermal oxidation of vanadium metal have been studied by X-ray photoelectron spectroscopy (XPS) using a direct anaerobic and anhydrous transfer from the glove box (O2 and H2O<1ppm), where the samples were electrochemically treated, to the XPS analysis chamber. Vanadium in the as-prepared oxide films is mostly (from 93 to 96% depending on samples) in a pentavalent state (V5+) with a stoichiometric O/V concentration ratio fitting that of V2O5. Four to seven percent of VO2 is also observed. After the 1st and the 2nd intercalation steps at E =3.3 and 2.8V versus Li/Li+, respectively, the V2p core level spectra evidence a partial reduction to V4+ states with a remaining concentration of 73 and 56% of V5+, in agreement with the intercalation of about 1/2mol of Li per V2O5 mol at each intercalation step. Intercalated lithium was observed at a binding energy of 56.1eV for Li1s. Changes of the electronic structure of the V2O5 thin film after intercalation are evidenced by the observation, at a binding energy of 1.3eV, of occupied V3d states (V4+) originally empty in the pristine film (V5+). The V2p and Li1s core level spectra show that the process of Li intercalation is partially irreversible. In the first cycle, 34 and 14% of the vanadium ions remain in the V4+ state after deintercalation at E =3.4 and 3.8V versus Li/Li+, respectively, indicating a partially irreversible process already after the 1st deintercalation. The analyses of C1s and O1s XP spectra show the formation of a solid–electrolyte interface (SEI). The analyzed surface layer includes lithium carbonate and Li-alkoxides.
This paper identifies the structural properties of a technological knowledge network and the role of major organizations in the network, and analyzes actual contents of technological knowledge flows in terms of organization-technology linkage, by targeting the field of organic solar cells (OSC). Network analysis and matrix analysis methods are used to achieve these purposes. The results show the small-world effect exists in the technological knowledge network of OSCs, and the organizations with high betweenness centrality lead the technological knowledge flows. We also find technological knowledge in classes 136 and 313 flows relatively actively in key organizations׳ network of OSCs. This means that technological knowledge regarding photoelectric batteries and electric lamp and discharge devices is mainly circulated between key organizations and indicates that the electronics or display sector will become a major consumer for early commercialization of OSCs. The target of analysis in this study is a patent citation network in the field of OSCs. Since we did not analyze all scientific publications, we cannot conclude that the results represent the entire flow of technological knowledge in that field. However, given that little attention has been paid to empirical studies of technological knowledge flows at the organizational level, this study makes an academic contribution by directly analyzing technological knowledge flows between organizations and presenting new taxonomic method based on centralities. The analytical process and methodology of this study, which include analysis of the structural properties of technological knowledge networks, matrix analysis and taxonomical grouping, and analysis of technological knowledge flows between key organizations, will be usefully applied to the analysis of technological knowledge networks in other fields.
Organic electrode materials are promising alternatives to transition-metal based intercalation compounds for the next generation of high-performance and sustainable batteries. Herein, a novel quinone-based organic, lithium salt of poly(2,5-dihydroxy-p-benzoquinonyl sulfide) (Li2PDHBQS), was successfully synthesized through a simple one-step polycondensation reaction, and applied as a cathode for Li–organic batteries. As an oligomeric lithium salt with average polymerization degree of 7, Li2PDHBQS combines the advantages of the O⋯Li⋯O coordination bond and increased molecular weight, thus solves absolutely the dissolution problem of active material in non-aqueous electrolytes, which has seriously hindered development of organic electrode materials. Benefiting from the high theoretical capacity, intrinsic insolubility, fast reaction kinetics of the quinone group, accelerated Li-ion transport and uniform blending with conductive carbon, as well as the stable amorphous structure, Li2PDHBQS shows superior comprehensive electrochemical performance including high reversible capacity (268 mA h g−1), high cycling stability (1500 cycles, 90%), high rate capability (5000 mA g−1, 83%) and high Coulombic efficiency (99.9–100.1%). Investigation of the structure–property relationship of Li2PDHBQS and its analogues also gives new insights into developing novel quinone-based organic electrode materials, for building better Li–organic or Na–organic batteries beyond traditional Li-ion batteries.
We present a design and synthesis of a hierarchical architecture of graphene oxide @ mesoporous carbon (GO@Meso-C) using graphene oxide @ metal-organic framework hybrid materials (GO@MOF-5) as both the template and precursor. Active sulfur is encapsulated into the GO@Meso-C matrix prepared via carbonize GO@MOF-5 polyhedrons for high performance lithium sulfur battery. The initial and 100th cycle discharge capacity of GO@Meso-C/S sulfur cathode are as high as 1122 mAh g−1 and 820 mAh g−1 at a current rate of 0.2C. The remarkably high special capacity and capacity retention rate indicate that the GO@Meso-C is a promising host material for the sulfur cathode in the lithium sulfur battery applications.
The synthesis of 40 polypeptides in mitochondria was found to be stimulated after transient exposure of human endothelial cells to sublethal levels of hydroperoxides, such as H2O2, using comparative two-dimensional polyacrylamide gel electrophoresis. Eleven proteins were identified; these include 60 kDa heat shock protein (HSP60), a mitochondrial type of 70 kDa HSP (mtHSP70), manganese-dependent superoxide dismutase (MnSOD), three metabolic enzymes in citric acid cycle, two components for respiratory chain complexes, a ribosomal protein for translation in mitochondria (RM12), and an unnamed protein. These proteins are involved in reduction-oxidation and protein biogenesis, suggesting that their synthesis, which is triggered under oxidative stress conditions, is aimed at playing a defensive role in mitochondria. Moreover, mtHSP70, HSP60, MnSOD, and RM12 were revealed as their respective precursor proteins with mitochondrial targeting sequences. The preproteins of HSP60 and mtHSP70 were transiently accumulated in mitochondria after the removal of H2O2 in a processing competent state, while the accumulated preprotein of MnSOD localized inside mitochondria and remained unchanged. Membrane potential of mitochondria and cellular ATP levels were unchanged under these conditions. Taken together, these results suggest that hydroperoxide stress leads to preprotein accumulation, possibly due to the impairment of the protein-processing system in mitochondria, independent of membrane potential dissipation and ATP depletion.
To investigate the effect of matrix, counter ions and cycling conditions on the properties of mixed iron oxides, CaFe2O4, Li0.5Ca0.5(Fe1.5Sn0.5)O4 and NaFeSnO4 have been synthesized and their electrochemical performance studied. CaFe2O4 shows a reversible capacity of ∼200mAhg−1 at 60mAg−1 and 12–50cycles in the range 0.005–3.0V, but shows slight capacity fading when the upper voltage is reduced to 2.5V. Li0.5Ca0.5(Fe1.5Sn0.5)O4 gives a reversible capacity of ∼450mAhg−1 in the voltage range 0.005–3.0V at a current density of 60mAg−1 over 5–30cycles and shows slight capacity-fading up to 50cycles. NaFeSnO4 displays drastic capacity-fading on cycling to 3.0V, but has very good cycling performance (310–340mAhg−1 for to 4–110cycles) on cycling between 0.005 and 1.0V at 60mAg−1. The mechanism of operation of the electrodes, as well as the beneficial effects of the presence of Ca ions and cycling up to a 3.0V cut-off in the Ca-ferrites, are discussed.
Summary Objective The authors investigated the potential effectiveness of biofeedback as a complementary treatment for PTSD. Design This exploratory study used heart variability biofeedback and determined its efficacy in treating PTSD through the use of two rating instruments, The Post-traumatic Stress Disorder Checklist (PCL)-Military version and the Zung Self-Rating Depression Scale. Active duty service members deployed to Iraq or Afghanistan were alternatively assigned to a treatment as usual control group and treatment as usual with the addition of biofeedback. The authors administered the two instruments before treatment and at the conclusion of three weeks of biofeedback therapy. Results Biofeedback did not produce a measurable improvement. A one way repeated measures analysis of variance (ANOVA) was used to examine change in PCL scores over time. There was a main effect for time, F(1, 36)=11.98, p <.001, indicating a decrease in PCL scores from baseline to three weeks for both the control and treatment group. Results demonstrated a nonsignificant main effect of group, F(1, 36)=.1.79, p =ns, and a nonsignificant group by time interaction, F(1, 36)=.2.59, p =ns. Similarly, for depression, results showed a significant main effect for time, F(1, 33)=10.26, p <.003, indicating a decrease in Zung scores from baseline to three weeks for both the control and treatment group. Results demonstrated a nonsignificant main effect of group, F(1, 33)=.385, p =ns, and a nonsignificant group by time interaction, F(1, 33)=3.52, p =ns. Conclusion The addition of biofeedback did not produce a measurable improvement in PTSD or depression scores in this exploratory study.
V-doped LiFePO4/C cathode materials were prepared through a carbothermal reduction route. The microstructure was characterized by X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy. The electrochemical Li+ intercalation performances of V-doped LiFePO4/C were compared with those of undoped one through galvanostatic intermittent titration technique, cyclic voltamperometry, and electrochemical impedance spectrum. V-doped LiFePO4/C showed a high discharge capacity of ∼70mAhg−1 at the rate of 20C (3400mAg−1) at room temperature. The significantly improved high-rate charge/discharge capacity is attributed to the increase of Li+ ion “effective” diffusion capability.
A microwave-assisted hydrothermal approach combined with carbothermal reduction has been developed to synthesize monodisperse porous LiFePO4/C microspheres, which possess the diameter range of 1.0–1.5 μm, high tap density of ∼1.3 g cm−3, and mesoporous characteristic with Brunauer–Emmett–Teller (BET) surface area of 30.6 m2 g−1. The obtained microspheres show meatball-like morphology aggregated by the carbon-coated LiFePO4 nanoparticles. The electrochemical impedance spectra (EIS) results indicate that carbon coating can effectively enhance both of the electronic and ionic conductivities for LiFePO4/C microspheres. The Li-ion diffusion coefficient of the LiFePO4/C microspheres calculated from the cyclic voltammetry (CV) curves is ∼6.25 × 10−9 cm2 s−1. The electrochemical performance can achieve about 100 and 90 mAh g−1 at 5C and 10C charge/discharge rates, respectively. As cathode material, the as-prepared LiFePO4/C microspheres show excellent rate capability and cycle stability, promising for high power lithium-ion batteries.
New product development (NPD) is a crucial process to keep a company being competitive. However, because of its inherent features, NPD is a process with high risk as well as high uncertainty. To ensure a smooth operation of NPD, the risk involved in the process need to be assessed and the uncertainty should also be addressed properly. Facing these two tasks, in this paper, the critical risk factors in NPD are first analyzed. Since Bayesian network is specialized in dealing with uncertainties, those risk factors are then modeled into a Bayesian network to facilitate the assessing of the risk involved in an NPD process. To generate the probabilities of different kinds of nodes in a Bayesian network, a systematic probability generation approach is proposed with emphasis on generating the conditional probabilities of the nodes with multi-parents. A case study is also given in the paper to test and validate the critical risk factors as well as the probability generation approach.
Publisher Summary No universal definition of the user experience exists. Definitions from researchers and practitioners extend all the way from examining neurological phenomena to macroeconomic behaviors. Somewhere between counting the firings of neurons and calculating profit and loss statements is a practical set of boundaries that defines what to consider in a design process. Usability is the practice of making things easy to use. It is often equated with user experience, but while bad usability can break a good product, good usability is insufficient to create a good experience. An experience can be usable without being useful or valuable to enough people to justify the expense of creating it. Any definition of the user experience has to take into account the totality of what people engaged in using a product or service consider part of their experience. This ranges from how easy the product is to use to associations they may have with the vendor selling the experience. This definition attempts to transcend ergonomic, attitudinal, and visual metrics to include all facets that an audience considers relevant to an experience. The goal is to align developers’ understanding of the role a product plays in a person’s life with how that person perceives the design of that product.
Polypropylene (PP)/polyethylene (PE) multilayer separators with cellular-like submicron pore structure for lithium-ion battery are efficiently fabricated by the combination of multilayer coextrusion (MC) and thermal induced phase separation (TIPS). The as-prepared separators, referred to as MC-TIPS PP/PE, not only show efficacious thermal shutdown function and wider shutdown temperature window, but also exhibit higher thermal stability than the commercial separator with trilayer construction of PP and PE (Celgard® 2325). The dimensional shrinkage of MC-TIPS PP/PE can be negligible until 160 °C. In addition, compared to the commercial separator, MC-TIPS PP/PE exhibits higher porosity and electrolyte uptake, leading to higher ionic conductivity and better battery performances. The above-mentioned fascinating characteristics with the convenient preparation process make MC-TIPS PP/PE a promising candidate for the application as high performance lithium-ion battery separators.