batterydata/paper-abstracts huggingface dataset:
Matching of metal hydride pairs has a significant influence on performance of thermal energy storage (TES) system. This article conducts a complete techno-economic analysis of screening metal hydride pairs (MgH2&LaNiAl and MgH2&TiFeMn). A mathematical model is developed to calculate the energy consumption, which is solved by COMSOL Multiphysics v5.1. Firstly, thermodynamic matching is analyzed to judge the energy consumption qualitatively. Further, a cost model of thermal energy is established to estimate the energy consumption cost. It is found that the charging energy consumption cost of MgH2&LaNiAl system is reduced to be zero due to a good thermodynamic matching, whereas that of MgH2&TiFeMn system accounts for as high as 63.8% of the cycle energy consumption cost. Based on the life cycle economic analysis, matching of MgH2&TiFeMn is considered to be a better selection due to a smaller levelized thermal storage cost (28 USD/kWhth), where two major expenses are the capital cost and energy consumption cost, 74.3% and 19.3% respectively. Therefore, a matching principle is concluded that screening metal hydride pairs for TES should be considered in two ways: firstly, the hydrogen storage cost due to the expensive price of low temperature metal hydride; secondly, the thermodynamic matching, which determines the energy consumption cost.
Filter media and industrial nonwoven supplier Hollingsworth & Vose has formed a new subsidiary company and is to add a manufacturing site in China, to support its long-term growth in the filtration, battery separator and other technical specialty markets.
Two kinds of carbon nanotubes (CNTs), i.e., short carbon nanotubes (CNTs-1) synthesized by co-pyrolysis method and long carbon nanotubes (CNTs-2) produced using common CVD technique were comparatively investigated as anode materials for lithium ion batteries via transmission electron microscope (TEM), high-resolution TEM and a variety of electrochemical testing techniques. The test results showed that the reversible capacities of CNTs-1 electrode were 266 and 170mAhg−1 at the current densities of 0.2 and 0.8mAcm−2, respectively, which were almost twice those of CNTs-2 electrode. The larger voltage hysteresis in CNTs-2 electrode was not only related to the surface functional groups on CNTs, but also to the surface resistance of CNTs, which results in greater hindrance and higher overvoltage during lithium extraction from electrode. The kinetics properties of these two CNTs electrodes were compared by AC impedance measurements. It was found that, both the surface film and charge-transfer resistances of CNTs-1 were significantly lower than those of CNTs-2; the lithium diffusion coefficient (D Li) of both CNTs electrodes decreased as the drop of voltage, but the magnitude of the D Li variation of CNTs-1 electrode was smaller than that of CNTs-2 electrode, indicating CNTs-1 exhibited higher electrochemical activity and more favorable kinetic properties during charge and discharge process.
Background: The early positive component of MLAERPs, occurring between 35 and 90ms after the stimulus (P50), may reflect a preattentive stage of information processing, and has been widely evaluated in schizophrenia. Many studies have shown P50 gating deficits in schizophrenia patients. We explore the relationship between P50 sensory gating and neuropsychological measures. Methods: P50 gating was measured in hundred and sixty patients with schizophrenia (DSM-IV / SCID) and sixty four control subjects. All patients were community dwelling and clinically stable. Neuropsychological assessment. We used a neuropsychological battery described elsewere (Sanchez-Morla et al., 2009). Six cognitive domanins were examined: speed of processing, executive function, working memory, sustained attention, verbal memory and visual memory. Results: 1. The overall MANOVA (F(1,217)=34.3; p<0.0001) indicated significant differences in neuropsychological function among patients with schizophrenia and control group. 2. In the group of patients with schizophrenia, parametric and nonparametric correlations revealed no significant relationships between P50 gating and performance in any of the 21 primary neurocognitive variables and any of the 6 neurocognitive domains. Neither there was any significant correlation in the control group. 3. When compared neurocognitive measures (primary variables and domains) in patients among the lowest vs highest quartiles of P50 ratio, no significant differences were observed. Discussion: We failed to detect relationship between P50 gating and performance across neurocognitive measures. This lack of association is very consistent taking into account the substantial power afforded by this large cohort of patients with schizophrenia.
In this work, Li2NaV2(PO4)3 is successfully synthesized by using a simple solid-state reaction method. Structural analysis shows that this sample is a hybrid product consisted of rhombohedral Li3V2(PO4)3 phase and rhombohedral Na3V2(PO4)3 phase As a cathode material for lithium ion batteries, Li2NaV2(PO4)3 exhibits an initial reversible capacity of 108.9mAhg−1 at 35mAg−1 in the potential range between 3.0 and 4.3V, with an average working potential at 3.75V. The lithium-ion diffusion coefficient in Li2NaV2(PO4)3 is measured to be 1.86–3.27×10−15 cm2 s−1. In addition, the electrochemical reaction between Li2NaV2(PO4)3 and Li is also investigated by various in-situ and ex-situ techniques. Viewed from the in-situ and ex-situ results, it is concluded that the electrochemical reactions of Li2NaV2(PO4)3 with Li are associated with the formation of rhombohedral LiV2(PO4)3 phase and rhombohedral NaV2(PO4)3 phase during the lithium ion extraction process and its reverse lithium insertion process is reversible for structural evolution. The highly stable structure ensures the electrochemical reversibility of Li2NaV2(PO4)3 cathode material in lithium ion batteries.
As a result of aging, the number of patients with cardiac implantable electronic device (CIED) requiring radiotherapy (RT) continues to rise. The aim of this work was to evaluate RT-related malfunctions of CIED in a cohort of patients who underwent RT in our clinic from June 2010 to December 2016. We retrospectively analyzed 93 RT treatments in 63 patients with CIEDs. Patients were treated with 3D conformal RT, intensity-modulated RT and stereotactic RT. We collected clinical characteristics of cancer, models of CIEDs, total RT dose to tumor and radiation energy. Radiation dose delivered to CIED and its dysfunctions after RT was evaluated. Subgroup analysis of 48 RT treatments (32 patients) on chest and neck plus on 13 RT treatments (12 patients) with 18 MV neutron-producing photon energy considered as high risk was performed. The number of treatments of patients with CIEDs increased from 0.3% in 2011 to 1.2% in 2016. Two patients, treated with 18 MV photon beam, with implantable cardioverter–defibrillators (ICDs) that received a maximum dose of around 2.1 Gy, experienced adverse events: a reprogramming of ICD when the patient reached a delivered dose to the tumor of 32 Gy, and an altered sensing function requiring replacement after 11 months from the end of RT. Nearly 2% of patients with CIEDs from high-risk patients subgroup had experienced a damage of the device. Close cooperation between radiation oncologists, cardiologists, medical physicists and radiation technologists is needed to achieve the best practice management in these patients.
Coiled springs (mainsprings) are coiled steel ribbons that have been used as a power source for centuries. A major disadvantage of mainsprings is that they do not deliver a uniform torque during unwinding. Theoretical analysis of mainsprings is notoriously difficult, and they are usually designed using well established rules of thumb. In service mainsprings are subjected to low cycle fatigue loading. They can fail either by breaking due to fatigue, or by shakedown into a shape where they no longer deliver adequate power. Some features of the behaviour of mainsprings used as power sources are described and illustrated by examples. In particular, the importance of correct lubrication is emphasised. The primary loading on a mainspring is a bending moment, but sequential biaxial loading can occur, as can biaxial stresses due to distortion at end fittings. A fracture mechanics approach to some aspects of mainspring behaviour is promising.
In this work, we successfully synthesize ordered Sn/CMK-3 nanocomposites by sonochemical method and carbonization process. XRD results verify that SnO2 has been completely reduced to metal Sn for the samples obtained at 800°C. Sn nanoparticles are good dispersed into the pore channels of ordered CMK-3 for Sn/CMK-3 nanocomposites according to the nitrogen adsorption–desorption isotherms. The lithium storage properties shows that the Sn/CMK-3 nanocomposites obtained at 800°C delivers an initial discharge capacity of 1450mAhg−1, and a reversible capacity as high as 674mAhg−1 after 50 cycles at a current density of 100mAg−1, much higher than those of the samples obtained at 600°C (1352 and 411mAhg−1, respectively). The Sn/CMK-3 nanocomposites obtained at 800°C also demonstrates an excellent rate capability with capacity of 546mAhg−1 even at a current density of 1000mAg−1 after 50 cycles. The improved lithium storage properties of Sn/CMK-3 nanocomposites obtained at 800°C can be attributed to a synergistic reaction between Sn nanoparticles and CMK-3 matrix, as well as the high crystallinity.
A maleic acid assisted sol–gel method was employed to synthesize LiNi0.8Co0.2O2 cathode materials, which are of interest for potential use in lithium batteries. Various synthesis conditions such as solvent, calcination time, calcination temperature, acid-to-metal ion ratio (R), and lithium stoichiometry were studied to determine the ideal conditions for preparing LiNi0.8Co0.2O2 with the best electrochemical characteristics. The optimal synthesis conditions were found to be an ethanol solvent with a calcination time of 12h at 800°C under flowing oxygen. The first discharge capacity of the material synthesized using the above conditions was 190mAh/g, and the discharge capacity after 10 cycles was 183mAh/g, at a 0.1C rate between 3.0 and 4.2V. Details of how varying initial synthesis conditions affected capacity and cycling performance of LiNi0.8Co0.2O2 are discussed.
The mechanism and kinetics of oxygen reduction were studied at such composite catalysts as PANI/C, PPy/C, transition metal oxides/C and PPy/C/transition metal oxides by the method of rotating disc electrode. It was shown that for the PANI/C and PPy/C catalysts there are almost no diffusion limits and the sluggish stage of the reaction is chemo sorption of oxygen at the polymer surface followed by desorption and formation of hydrogen peroxide (a two-electron mechanism). In contrast, for the inorganic composites transition metal oxides/C the limiting stage is oxygen diffusion, whereas the calculated effective number of electrons is approximately 3.0. In organic/inorganic composite catalysts of the PPy/C/transition metal oxides type oxygen reduction proceeds by a mixed diffusion–adsorption mechanism to form water (a four-electron mechanism). The calculated effective number of electrons for such available catalysts is 3.8 in alkaline electrolytes, which, by efficiency, approaches the ideal value 4.0 for noble metals.
P2-phase Na0.74CoO2 cathode material prepared by a solid-state method exhibits the specific discharge capacity of 107mAhg−1 at 0.1C with good cycling performance for rechargeable sodium ion batteries. The voltage polarization between charging and discharging at 0.1C rate is about 150–250mV and the coulombic efficiency in each cycle is about 89%. The expansion and compression in c-axis of the Na x CoO2 unit cell during the Na intercalation/deintercalation is revealed by ex situ XRD. XPS and in situ XAS data directly confirm that deintercalation/intercalation of Na ions from/into the layered structure proceeds with the Co3+/Co4+ redox reaction.
Electrode materials with a large internal surface area, tunable pore size, efficient transport of electrons and high ion-accessibility are highly desired in the development of advanced flexible supercapacitors. Recently, transition metal sulfides with rationally designed nanostructures have attracted considerable attention as electrode materials for supercapacitors. In this study, we report the synthesis of Zn0.76Co0.24S/NiCo2S4 nanosheets grown on carbon cloth using a two-dimensional bimetallic Zn/Co zeolitic imidazolate framework (named as Zn/Co-ZIF-L) as a precursor through a simple and cost-effective chemical solution process. The ZIF-derived Zn0.76Co0.24S/NiCo2S4 electrode nanosheets deliver an ultrahigh specific capacitance of 2674 F g−1 at 1 A g−1, a superior ratio performance and cycle stability. Furthermore, the as-fabricated Zn0.76Co0.24S/NiCo2S4//AC all-solid-state asymmetric supercapacitor (ASC) achieves a maximum energy density of 48.1 Wh kg−1 as well as a power density of 837 W kg−1, and a superior cycling performance of 91% retention after 5000 cycles. The detailed electrochemical kinetic analysis demonstrates that the total capacitance of Zn0.76Co0.24S/NiCo2S4 is derived from its capacitive-effective charge storage mechanism. This ZIF-derived strategy provides a reasonable and simple way to synthesize transition metal sulfides as potential active materials for next-generation flexible supercapacitors.
The influences of partial substitution of Mn in LiMn2O4 with Cr3+ and Li+ on their charge/discharge profiles were quite different: Cr3+ affected it only in the high-voltage region, while Li+ showed in the both high and low voltage regions. Either Cr3+ or Li+ doping significantly improved the storage and cycling performance of spinel LiMn2O4 at the elevated temperature, specially both doped spinel. Li1.02Cr0.1Mn2O4 shows very low rate of capacity rention, 0.1% per cycle, and maintained a steady discharge capacity of 114mAh/g, 95% of the initial discharge capacity over 50 cycles at 50°C. The chemical analysis and X-ray diffraction measurement indicate that the capacity losses of LiMn2O4 is mainly due to the dissolution of Mn into electrolyte, further transformation to lithium-rich spinel Li1+x Mn2O4. The improvements in their electrochemical profiles for the Cr3+ and Li+ modified spinel is attributed to that the partial substitution of Mn stabilize its structure, thus minimizing the dissolution of Mn into electrolyte, as well as maintaining its original morphologies.
To describe a new molar-incisor hypomineralization (MIH) severity scoring system (MIH-SSS) that focuses on the defects’ severity and to assess the system’s validity and reliability over 3 years.
Liquid-electrolyte sodium-sulfur battery operated at room temperature is encountering challenges brought by the complex sulfur redox reactions, including (i) the dissolved polysulfide intermediates trigger serious side reactions on Na anode surface; (ii) the short-chain sulfide precipitation exhibits sluggish kinetics and the sulfur utilization is generally below 50% with unclear reasons. In this work, employing an ion selective polybenzimidazole-based separator we successfully suppress the polysulfide corrosion on the Na anode, which allows the investigation of the precipitation reaction. Combining DFT calculation and characterization techniques, we determine Na2S2 particles as the final discharge product and reveal that Na2S2 passivation is the predominant attributes of large polarization and capacity fading. To address these issues, we present the use of a bifunctional NaI-P2S5 based electrolyte additive, which (i) improves the Na2S2 precipitation kinetics by forming soluble Na2S2-P2S5 complex and (ii) promotes the dissolution of Na2S2 by the chemical mediation of I−/ I 3 − . As a result, a much improved capacity retention (92.9% for 50 cycles at 0.2C) is attained, which sheds light on enabling the stable operation of sodium-sulfur batteries via combining advanced separator and electrolyte engineering strategies.
Lithium ion battery applications such as transportation or renewable energies require cost effective, environmentally friendly and high capacity materials. Conversion reaction with iron based materials at positive electrode is a promising route to reach this target. In this work, iron hydroxyl-fluoride conversion coatings are prepared by an electrochemical way. The structure of the produced coatings is nano-porous with a pore diameter of about 75 nm. An impedance-based methodology is proposed for in-situ characterisation of the conversion coatings during the preparation procedure and enables to optimize the process parameters to get a 3D nano-porous structure. The cycling tests performed in coin-cell versus lithium reference electrode show a promising cycling behaviour for the prepared nano-porous coatings.
In sentiment analysis, a finer-grained opinion mining method not only focuses on the view of the product itself, but also focuses on product features, which can be a component or attribute of the product. Previous related research mainly relied on explicit features but ignored implicit features. However, the implicit features, which are implied by some words or phrases, are so significant that they can express the users’ opinion and help us to better understand the users’ comments. It is a big challenge to detect these implicit features in Chinese product reviews, due to the complexity of Chinese. This paper is mainly centered on implicit features identification in Chinese product reviews. A novel hybrid association rule mining method is proposed for this task. The core idea of this approach is mining as many association rules as possible via several complementary algorithms. Firstly, we extract candidate feature indicators based word segmentation, part-of-speech (POS) tagging and feature clustering, then compute the co-occurrence degree between the candidate feature indicators and the feature words using five collocation extraction algorithms. Each indicator and the corresponding feature word constitute a rule (feature indicator → feature word). The best rules in five different rule sets are chosen as the basic rules. Next, three methods are proposed to mine some possible reasonable rules from the lower co-occurrence feature indicators and non indicator words. Finally, the latest rules are used to identify implicit features and the results are compared with the previous. Experiment results demonstrate that our proposed approach is competent at the task, especially via using several expanding methods. The recall is effectively improved, suggesting that the shortcomings of the basic rules have been overcome to certain extent. Besides those high co-occurrence degree indicators, the final rules also contain uncommon rules.
The preparation of a stoichiometric dispersion of nanostructured LiFePO4 clusters with intimate contact to carbon is described. This material exhibits outstanding performance for hybrid energy storage applications. A synthetic process, involving a novel single molecular source precursor, was developed and used to infiltrate a structured mesoporous carbon template. Subsequent optimisation of the infiltration process, reductive pyrolysis and secondary dispersion of the active materials for electrode coatings gave highly effective LiFePO4/C composite electrodes suitable for high power applications. The materials were found to have surface areas in excess of 800 m2 g−1 and TEM revealed an intimate contact to the carbon matrix as a result of the single source precursor employed. Extensive electrochemical performance evaluation, at rates exceeding 20 C, confirmed a resilient stable material capable of delivering exceptional high rate performance which is attributed to the periodic, interconnected mesopores (5–6 nm) and also the intimate LiFePO4/C content delivered from the single source precursor. Galvanostatic charge–discharge cycling demonstrated the materials' excellent stability and high utilization, with a specific discharge capacity of 163 A h kg−1 (close to theoretical unity of 170 A h kg−1) at 0.2 C and 128 A h kg−1 at 23 C, an exceptional result relative to lower surface area analogues. Power delivery was almost three times that of commercial LiFePO4 at 10 C. These materials are well suited for application in high power energy storage devices including high power lithium batteries and hybrid devices.
In this paper, we prepared a phosphazenic compound triethoxyphosphazen-N-phosphoryldiethylester (PNP) by a facile method and characterized as a flame-retarding electrolyte additive for lithium ion batteries. The flammability and electrochemical performance of the PNP-containing electrolyte were investigated. The self-extinguishing time (SET) value of 10% PNP in the electrolyte is 40% decreased compared to base electrolyte, implying strong inhabitation to the flammability. The electrochemical performances of MCMB/Li, LiFePO4/Li and LiMn2O4/Li half-cells in 10% PNP electrolyte exhibit considerable capacity, coulombic efficiency and cycling stability compared to the base electrolyte. Therefore, PNP as flame-retarding additive is a promising candidate combining efficient flame retardancy and good electrochemical performance for safer lithium ion batteries.
In this paper we report the properties of the Fe(II)/Fe(III) reaction in a deep eutectic solvent based on choline chloride and ethylene glycol. This reaction is shown to be facile using a wall-jet electrode and rotating disc electrode. The deposition and stripping of iron exhibits equally slow kinetics as in aqueous systems. Using these two reactions an all-iron redox flow battery based on ionic liquids is reported for the first time. An energy efficiency of 37% is attained at a current density of 0.5mAcm−2. A Zn(II)–Fe(II) complex is shown to form when zinc is oxidized by Fe(III). When this complex is applied in a redox flow battery energy efficiencies of 78% are achieved at a current density of 0.5mAcm−2.
484 new and 1908 aged lithium-ion cells out of two identical battery electric vehicles (i.e. 954 cells each) were characterized by capacity and impedance measurements to yield a broad set of data for distribution fit analysis. Results prove alteration from normal to Weibull distribution for the parameters of lithium-ion cells with the progress of aging. Cells with abnormal characteristics in the aged state mostly exhibit lower capacities as compared to the distribution mode which is typical for the left-skewed Weibull shape. In addition, the strength of variation and the amount of outliers both are generally increased with the aging progress. Obtained results are compared to vehicles' operational data to provide recommendations with the aim to minimize the increasing parameter spread. However, neither temperature gradients in the battery pack nor an insufficient balancing procedure were determined. As the appearance of cells with suspicious parameters could not be assigned to local weak spots of the battery pack, a random and inevitable type of origin is assumed. Hence, the battery management system must ensure to detect outliers in a reliable manner and to balance resulting drifts of cells' states of charge to guarantee a safe battery storage operation.
Publisher Summary The mobile telephone has found a niche as a device that provides safety and a sense of security in a variety of situations. For those who have chronic conditions, the device allows a broader freedom of movement and a sphere of action. The device is seen as being useful in acute problems, ranging from punctured tires to life-threatening situations. This aspect of mobile telephony has been abstracted to the point that the mobile telephone symbolizes security. But mobile telephone can also threaten public safety and can be used for various criminal activities. The use of phone while driving has increased the possibility of having an accident. While the link between driving and telephoning is commonly understood, it is also commonly ignored. The use of the mobile telephone has found a place in the free spaces of user's schedules. Using the phone in these situations allows attending to the small coordination chores one would otherwise do in more stationary settings.