batterydata/paper-abstracts huggingface dataset:
An improved model to analyze the partial molar entropy step between stage II and stage I for lithium intercalation in graphite, based in statistical mechanics, is presented. At difference with our previous formulation, which assumed a priori heterogeneities, the present model considers the more realistic case of induced heterogeneities. The present work shows that, similarly to considerations made in the literature with intercalation cathode materials, most of the partial molar entropy changes for Li insertion into graphite may be explained on a configurational basis. The interaction between ions intercalated in a same layer of graphite can be inferred to be strongly attractive, as was assumed in the literature for the simulation of voltammetric profiles.
The authors regret the omission of the following acknowledgement: “The authors A. Manuel Stephan and Shruti Suriyakumar gratefully acknowledge DST, New Delhi for funding through SERB (EMR/2014/000472)” The authors would like to apologise for any inconvenience caused.
Complex immunophenotypic repertoires defining discrete adipose-derived stem cell (ASC) subpopulations may hold a key toward identifying predictors of clinical utility. To this end, we sorted out of the freshly established ASCs four subpopulations (SPs) according to a specific pattern of co-expression of six surface markers, the CD34, CD73, CD90, CD105, CD146, and CD271, using polychromatic flow cytometry.
Nowadays, the wide-spread adoption of supercapacitors has been hindered by their inferior energy density to that of batteries. Here we report the use of our pyrolytic-carbon-coated carbon nanotube foams as lightweight, compressible, porous, and highly conductive current collectors in supercapacitors, which are infiltrated with chemically-reduced graphene oxide and later compressed via mechanical and capillary forces to generate the active electrodes. The pyrolytic carbon coatings, introduced by chemical vapor infiltration, wrap around the CNT junctions and increase the surface roughness. When active materials are infiltrated, the pyrolytic-carbon coatings help prevent the π-stacking, enlarge the accessible surface area, and increase the electrical conductivity of the scaffold. Our best-performing device offers 48% and 57% higher gravimetric energy and power density, 14% and 23% higher volumetric energy and power density, respectively, and two times higher knee frequency, than the device with commercial current collectors, while the “true-performance metrics” are strictly followed in our measurements. We have further clarified the solution resistance, charge transfer resistance/capacitance, double-layer capacitance, and Warburg resistance in our system via comprehensive impedance analysis, which will shed light on the design and optimization of similar systems.
While in the developed countries electrification is paving the way for progress and prosperity, nowadays electricity is still not accessible for about 18% of the world’s population. Lack of power grids is the main reason that prevents millions in remote areas in developing countries from using electricity for the daily basic needs. PV systems provide an effective solution for these regions, but affordability remains an issue. This barrier can be widely overcome on the short term by limiting PV power supply to very high added value applications and by properly exploiting innovations, especially in energy efficiency and cost reductions. Additional to that, the long-term perspectives of off-grid PV are very favourable based on its ongoing technological improvements and cost reductions. This paper studies four off-grid PV cases of which each could cover a combination of basic energy needs regarding light, cooking, food conservation and electronic appliances. Case I considers a system that supplies power for LED lamps and electronic devices. Accordingly, Case II adds a fridge and Case III an electric rice cooker to Case I, while Case IV adds both. The paper elaborates on available technologies and future developments regarding all components in order to assess the long term evolution and potential of these applications, most specifically how their affordability would evolve over time. The modelling and optimization of the four cases are performed using the software iHOGA, which is an efficient tool to provide the lowest cost solution for off-grid PV systems. The use of iHOGA for the four cases and the installation years 2020, 2030 and 2040, taking thereby into account different developing regions, provide an evolutionary techno-economic assessment of these applications and a clear picture about the developments to be expected from off-grid PV in general.
Electromotive force (EMF) voltage curves are regularly determined to facilitate in-depth understanding of aging mechanisms of C6/LiFePO4 batteries during cycling. The irreversible capacity losses under various cycling conditions and temperatures are accurately obtained from the extrapolated EMF curves and are found to increase with cycle number and time. A new mathematical extrapolation method is proposed to distinguish between calendar ageing and cycling-induced ageing. The capacity losses due to calendar aging are obtained by extrapolating the total irreversible capacity losses to zero cycle number. It is found that calendar ageing increases logarithmically in time. On the other hand, cycling-induced ageing is accurately determined by extrapolating the capacity losses to zero time. In this case the capacity losses are found to increase linearly with cycle number. It is furthermore found that iron dissolution from the cathode at 60°C and the subsequent deposition onto the anode enhances significantly the SEI formation on the graphite electrode and, consequently, battery ageing. Interestingly, the graphite electrode decay has been quantified in much more detail, by analyzing the d V E M F / d Q curves. The analyses show that the electrode decay can be related to both the structural deterioration and the inter-layer surface blockage of the graphite electrode, as has also been experimentally confirmed by Raman and XPS spectroscopy.
Investigation on solid state rechargeable magnesium batteries are considered important similar to lithium batteries. In view of negligible hazard and less reactivity of the magnesium, in comparison with lithium, studies on rechargeable magnesium batteries are expected to have a wide scope in future. In the present investigations, decoupled ion conduction of poly(vinyl alcohol) (PVA)-based Mg-conducting solid polymer electrolytes (SPEs) is essential component of the studies. In common SPEs, ion transport has mostly been associated with the segmental motion of the polymer, so significant conductivity is only observed above the glass transition temperature of the system. But the results of ac impedance spectroscopy, FT-IR, XRD and AFM indicated that prepared PVA-based Mg-conducting SPE shows ionic transport decoupled from polymer segmental motion and high ionic conductivity at room temperature.
The effects of particle size, chemical composition and cycling potential range on the electrochemical properties of micro-sized Sn–Sb electrodes were investigated in terms of initial irreversible capacity, rate-capability and cycling stability. Large particle sized SnSb electrode shows a low initial irreversible capacity and a relatively good cyclic performance when charged/discharged at 100mAhg−1 due to the low specific surface area and loose structural characteristics of SnSb particles. When charged and discharged at high current density, large particle sized SnSb electrode displays a fast capacity fading compared to the small sized one due to the long diffusion distance of Li-ions. The Sn/Sb ratio has effect on the cycling stability of electrodes. Sn-riched and Sb-riched Sn–Sb electrodes exhibit fast capacity decline while sample with pure SnSb intermetallic phase shows a relatively good cycling stability. To increase the lower limit of cycling potential range cannot improve the cyclic performance while to decrease the upper limit to 0.8V can control the cycling stability of SnSb electrode significantly. The Sb component is considered to be the main cause of the capacity fading of Sn–Sb electrode.
A star-like hyperbranched β-cyclodextrin is designed and synthesized for the solid polymer electrolyte of all-solid-state sodium batteries by grafting β-cyclodextrin with multiple oligo(methyl methacrylate)-block-oligo(ethylene glycol) methyl ether methacrylate short chains. Complexing this star-like hyperbranched β-cyclodextrin with sodium trifluomethanesulfonate salt leads to a self-standing, transparent, and flexible solid polymer electrolyte film. It is found that this solid polymer electrolyte exhibits superior thermal stability, excellent mechanical properties at the even elevated temperature and good interfacial stability against Na metal electrode. Especially, ascribing to the unique three-dimensional structure of the star-like hyperbranched β-cyclodextrin, a solid polymer electrolyte formed with the optimized star-like hyperbranched β-cyclodextrin containing 69.3 wt.% oligo(ethylene glycol) methyl ether methacrylate shows an ionic conductivity of 1.3 × 10−4 S cm-1 at 60 °C and a wide electrochemical window of 5.2 V vs. Na+/Na, which are superior to those of the previously reported solid polymer electrolytes. The all-solid-state Na/NaNi1/3Fe1/3Mn1/3O2 cell shows high first discharge capacity (102.4 mAh g−1 at 0.1C), good reversibility and excellent cycling performance (with 87.8% capacity retention after 80 cycles at 0.1C) at 60 °C. All the results indicate that the star-like hyperbranched β-cyclodextrin is a promising polymer for the solid polymer electrolyte of all-solid-state sodium batteries.
Soft tissue sarcomas (STS) constitute a heterogeneous category of soft tissue neoplasia composed mostly of uncommon tumors of diverse histology, different biology and varied outcomes. Substantial developments in immunohistochemistry (IHC), cytogenetics and molecular genetics of STS have caused a significant change in the classification and diagnosis of these tumors with a direct implication for clinical management and prognosis. In this review we discuss newer developments impacting diagnosis and prediction.
The life cycle of a solar park made using organic photovoltaic (OPV) technology is assessed here. The modules have been fabricated in a pilot scale plant and they have been installed together with other components to evaluate the balance of system, in a solar park located in Denmark. Three possible waste management practices have been contemplated for the end of life of the solar park: recycling, incineration or the average local mix. The assessment of the environmental impacts of such a system reveals that silver used in the electrodes is overall the largest source of impacts, such as chemical pollution and metal depletion. The establishment of resource recovery systems for the end-of-life management of the OPV modules is therefore crucial to reduce overall environmental impacts. Liability on the manufacturers or on the operators should be implemented. The electricity produced from OPV solar parks yields similar footprints to other traditional energy technologies; e.g. coal and natural gas. However, when the efficiency of the OPV modules is increased from 1% to 5% they are comparable to other mature PV technologies already on the market. The effects of outsourcing or exporting the production of the OPV modules from Denmark to China have additionally been studied to determine the most advantageous configuration. The stakeholders should aim at anchoring the manufacturing of solar parks in countries with stringent emission standards and/or high technology efficiencies, e.g. Denmark, and at deploying them in countries with high solar radiation to maximise the environmental benefits of the PV technology.
This chapter stresses the importance of drilling the basics. It begins with a thorough review of Ohm's Law (voltage equals current multiplied by resistance) and its applications. The next foundational formula explained is the voltage divider rule, followed by Thevenin's theorem, each of which is illustrated with plentiful examples and figures. While still applying these basics formula, the discussion moves to various relationships and interactions among voltage and current, expanding on alternating current (AC) and direct current (DC); capacitors and inductors; low-pass filters, high-pass filters, and active filters; and magnetic fields and electric fields. The chapter concludes with a brief discussion of control theory in order to illuminate the concept of systems, step input, feedback, and open-loop gain versus closed-loop gain.
Semi-solid flow batteries (SSFBs) provide a highly scalable energy storage alternative for the reliable use of intermittent renewable energy sources. In this work, a new pseudo three-dimensional (P3D), multi-scale and multi-physics approach to the modeling of SSFBs is presented which includes the correct way to model flowing active particles. Two coupled continuum domains; one representing the battery and another representing the electrochemically active particles, are used as the computational solution strategy, to resolve the characteristic multi-scale electrochemical phenomena. In modeling the flowing particles, solid-state diffusion is applied as the single transport mechanism, contrary to previous investigations which included convection/advection. Time dependent voltage profiles, as well as spatial distributions of the state of charge in the SSFB active particles are herein examined and a Ragone plot for a SSFB is unveiled for the first time. Although presented in the case of a nickel-metal hydride SSFB, this P3D model framework is adaptable to any other SSFB chemistry, based on Li-ion or Na-ion active materials for example.
The discharge potential behavior of lithium-manganese dioxide cells designed for implantable cardiac defibrillators was characterized as a function of extent of cell depletion for tests designed to discharge the cells for times between 1 and 7 years. The discharge potential curves may be separated into two segments from 0≤ x ≤∼0.51 and ∼0.51≤ x ≤1.00, where x is the dimensionless extent of discharge referenced to the rated cell capacity. The discharge potentials conform to Tafel kinetics in each segment. This behavior allows the discharge potential curves to be predicted for an arbitrary discharge load and long term discharge performance may be predicted from short term test results. The discharge potentials may subsequently be modeled by fitting the discharge curves to empirical functions like polynomials and Padé approximants. A function based on the Nernst equation that includes a term accounting for nonideal interactions between lithium ions and the cathode host material, such as the Redlich–Kister relationship, also may be used to predict discharge behavior.
A simple one-step surfactant-free hydrothermal approach is presented for the facile synthesis of ultrathin 2D MoS2/graphene heterostructure (rGO@MoS2) assembled foam-like structure. The morphology and structure of the rGO@MoS2 nanocomposite are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). It is found that numerous of ultrathin MoS2 nanosheets are homogeneously self-assembled on the surface of the foam-like reduced graphene oxide which acts as the skeleton of the nanocomposite. The electrochemical performance of the composite electrode is investigated. Due to countless exposed active sites of the ultrathin 2D MoS2 nanosheets and rapid ion diffusion and electron transport of the foam-like reduced graphene oxide with high strength and large specific surface area, the rGO@MoS2 composite shows superior electrochemical performance based on the cycling stability (retaining 657mAhg−1 after 150 cycles while retaining 110mAhg−1 after only 60 cycles of MoS2), and specific capacity (achieving more than 786mAhg−1 at 100mAg−1) compared with the pure MoS2 when used as electrode materials in LIBs.
In this study, (pentafluorophenylpropyl)trimethoxysilane (PFPPS) is grafted on a nickel-doped manganese spinel (LiNi0.5Mn1.5O4, LNMO) surface to suppress the failure modes in the 5-V positive electrode; electrolyte oxidation/film deposition, acid generation, and metal (Ni and Mn) dissolution. Vapor-phase molecular layer deposition is used to deposit a uniformly covered PFPPS layer on the LNMO surface. When the Li/LNMO cell is cycled at 3.5–4.9 V (vs. Li/Li+), the PFPPS moiety on the LNMO surface remains intact (not oxidized) under the highly oxidizing condition. Several beneficial features are observed with the PFPPS grafting. The oxidative electrolyte decomposition is mitigated, which increases the Coulombic efficiency of the Li/LNMO cell. Consequently, the surface film deposition and cell polarization are reduced, improving the capacity retention. Moreover, the acid generation and metal dissolution are also mitigated.
Much of the current research into metal hydride (MH) electrodes follows the principle that the materials should be composed of hydrogen-absorbing elements (A) and non-hydrogen-absorbing elements (B). This classical design principle, however, severely limits the potential capacities of the MH electrodes (typically <400 mA h g−1). Herein, we demonstrate a fundamentally new strategy to design high capacity MH electrodes without using B elements by inducing synergism in the dehydrogenation process. Mg24Y5 thin films, which are composed of two strong hydrogen-absorbing elements, achieve an exceptional electrochemical hydrogen storage capacity of ∼1500 mA h g−1 (5.6 wt%). All the absorbed hydrogen, including extremely stable H in YH2, can be reversibly desorbed through thermodynamic synergism. The present study provides enlightening insights to design high capacity MH electrodes and therefore enables the revival of Ni–MH batteries, and the emergence of next generation MH–air batteries.
Purpose We evaluated the long-term medical and economic benefits of vagus nerve stimulation (VNS) therapy for 704 adults and children with epilepsy. A pre–post analysis was conducted using Hospital Episode Statistics (HES) data (April 2008–July 2014). Seven hundred and four patients with epilepsy diagnoses (ICD-10 G40.x or G41.x), one or more procedures for vagus nerve stimulator implantation, and six or more months of available HES data pre- and post-VNS were selected. The pre-VNS period averaged 39.1months. The post-VNS period extended from implantation to device removal, death, or study end (up to six years), with a mean duration of 36.4months. Incidence rate ratios (IRRs) and cost differences (£2014) were estimated. Mean age was 28.3years. Results Inpatient admissions decreased post-VNS compared with pre-VNS (adjusted IRR=0.81, P<0.001). Overall, outpatient consultations increased post-VNS compared with pre-VNS (adjusted IRR=1.34, P<0.001). However, outpatient consultations exhibited a decreasing trend in the post-VNS period (adjusted IRR=0.96, P<0.001), suggesting that much of the increased outpatient activity in the post-VNS period relates to follow-up management of the VNS device in the immediate period following implantation, with comparable outpatient resource burden at 36months post-VNS. No significant changes in clinical events were observed; however, average epilepsy-related medical costs were lower post-VNS than pre-VNS (adjusted cost difference −£110 quarterly, P=0.001). Conclusions Vagus nerve stimulation is associated with increased outpatient resource utilization and decreased inpatient admissions, with a reduction in long-term epilepsy-related medical costs post-implantation.
Histidine decarboxylase (Hdc) is required for the endogenous production of histamine, but its role in tumorigenesis is unclear. Yang et al. now report that Hdc-deficient mice develop more tumors in models of chemically induced carcinogenesis, associated with an increased recruitment of immature myeloid cells to the tumors and higher amounts of interleukin-6. The authors further show that Hdc deficiency inhibits myeloid cell maturation and that exogenous histamine promotes monocyte differentiation and suppresses tumor growth.
Micromachined solid-oxide fuel cells (μSOFCs) are among a class of devices being investigated for portable power generation. Optimization of the performance and reliability of such devices requires robust, scale-dependent, design methodologies. In this first analysis, we consider the structural design of planar, electrolyte-supported, μSOFCs from the viewpoints of electrochemical performance, mechanical stability and reliability, and thermal behavior. The effect of electrolyte thickness on fuel cell performance is evaluated using a simple analytical model. Design diagrams that account explicitly for thermal and intrinsic residual stresses are presented to identify geometries that are resistant to fracture and buckling. Analysis of energy loss due to in-plane heat conduction highlights the importance of efficient thermal isolation in microscale fuel cell design.
Ionic conductivity, mechanical stability and electrochemical property were examined on the poly ethyleneoxide (PEO) based cross-linked gel polymer electrolyte. Bisphenol A ethoxylate diacrylates (BPAEDA) with different numbers of ethylene oxide units (n=4, 15) were used as cross-linkers. The curing kinetics of the cross-linker was examined by an FT-IR study with two types of initiators and at different curing temperatures. Higher conductivity was observed for the longer ethylene oxide unit. Conductivity of the polymer electrolyte prepared from BPAEDA (n=15) and liquid electrolyte (70wt.%) was 3.47×10−3 S/cm at 30°C. Improved tensile strength and elongation at break were realized from the polymer electrolyte using BPAEDA as a cross-linker. Electrolyte having higher cross-linking density showed higher tensile strength, but showed decreased flexibility. The stability of the polymer electrolyte against electrochemical oxidation could be extended to larger than 4.5V (versus Li/Li+). Lithium cycling efficiency of the polymer electrolyte was about 80%.
Introduction Gestures are important for nonverbal communication and were shown to be impaired in schizophrenia. Two categories of gestures can be differentiated: pantomime on verbal command and imitation of seen gestures. There is evidence that the neural basis of these domains may be distinct, pantomime being critically dependent on prefrontal cortex function. The aim of the study was to investigate gestural deficits in schizophrenia and their association with frontal lobe function and motor performance. Methods In 30 schizophrenia patients, gesture performance was assessed by the comprehensive Test of Upper Limb Apraxia (TULIA) using previously determined cut-off scores. The ratings of videotaped gesture performance were blinded. In addition, a battery of rating scales on frontal lobe function, parkinsonism, dyskinesia, catatonia and instrumental measures of gross and fine motor performance were assessed. Results Pantomime deficits were found in 40% and imitation deficits in 23% of the patients. Patients with gestural deficits had poorer frontal cortex function, more catatonic symptoms, and more severe psychopathology. Furthermore, trends indicated an association with a more chronic course of the illness. Pantomime was linked to frontal lobe function whereas imitation was associated with catatonic symptoms and gross motor performance. Conclusions Pantomime is frequently impaired in chronic schizophrenia and may critically depend on motor planning, reflecting a further example of brain disconnectivity in schizophrenia.