batterydata/paper-abstracts huggingface dataset:
Electrochemical properties of (polyethylene oxide) (PEO)/lithium trifluoromethanesulfonate (LiTf)/ethylene carbonate (EC)/sepiolite extruded composite electrolytes were studied. Appreciable electrochemical stability of 4.5 V at 70 °C was observed for polymer composite membranes with d-α-tocopherol-polyethylene glycol 1000 succinate-coated sepiolite fillers. Lithium plating/stripping analysis indicated no evidence of dendrite formation with good interfacial properties which were further confirmed by postmortem analysis of the cells. Solid state NMR studies show the presence of two Li+ population in the membranes. The feasibility of these electrolytes has been shown with LiFePO4 cathode materials. Initial discharge capacity of 142 mAh/g was observed remaining at 110 mAh/g after 25 cycles with a coulombic efficiency of 96%. The upscaling of these polymers can be easily achieved by extrusion technique and the capacity can be improved by varying the cathode architecture.
This article discusses the evaluation of the capacity of a person to make informed decisions about financial matters, independent living, and informed consent for medical treatment and research. Determination of capacity is a function for which most physicians have little training. The determination of competency for a general medical patient may be assessed by a combination of a bedside mental status examination such as the MMSE and a questionnaire such as the Aid To Capacity Evaluation (ACE 1999). For patients with focal neurological deficits such as aphasia, further evaluation of specific cognitive and language functions is needed; Alexander (Arch Neurol 45:23–6, 1988) suggested 7 specific functions to be assessed. Finally, in dementing illnesses, evaluation by the MMSE and a questionnaire such as the CCTI, or Capacity to Consent to Treatment Instrument (Marson et al. Arch Neurol 52:949–54, 1995) is needed. Dementia includes several separate syndromes of neurodegenerative disease, and in many of these conditions, focal deficits such as aphasia may necessitate a more thorough neuropsychological evaluation.
The electrochemical stability and conductivity of LiPF6 and lithium bis(oxalato)borate (LiBOB) in a ternary mixture of ethylene carbonate (EC), ethyl methyl carbonate (EMC) and diethyl carbonate (DEC) were compared. The discharge capacities of LiMn2O4/Li cells with the two electrolytes were measured at various current densities. At room temperature, LiMn2O4/Li cells with the electrolyte containing LiBOB cycled equally well with those using the electrolyte containing LiPF6 when the discharge current rate was under 1C. At 60°C, the LiBOB-based electrolyte cycled better than the LiPF6-based electrolyte even when the discharge current rate was above 1C. Compared with the electrolyte containing LiPF6, in LiMn2O4/Li cells the electrolyte containing LiBOB exhibited better capacity utilization and capacity retention at both room temperature and 60°C. The scanning electron microscopy (SEM) images and the a.c. impedance measurements demonstrated that the electrode in the electrolyte containing LiBOB was more stable. In summary, LiBOB offered obvious advantages in LiMn2O4/Li cells.
Semantic memory impairments have been reported extensively in people with schizophrenia. Inefficient search and retrieval strategies, due to an executive dysfunction, rather than a primary loss of semantic knowledge are a primary candidate for such impairments. In order to test this hypothesis we compared the performance of 20 patients meeting DSM-IV-TR criteria for schizophrenia with that of 20 healthy controls and 10 patients with acquired brain injury (ABI) with a dysexecutive syndrome. Seventy percent of the people with schizophrenia and 100% of the ABI patients in this study met criteria for executive impairment. However, the two groups performed significantly differently on a range of semantic memory tests. Whereas 45% of the patients with schizophrenia met criteria for distorted semantic category boundaries (n.b. overinclusion), this was true for only 10% of the ABI patients. In addition, no correlation was found between severity of executive dysfunction and tendency to overinclude in the schizophrenia group. This pattern of neuropsychological findings suggests that overinclusion, or disorganized semantic categorization procedures, in schizophrenia does not result from a classical executive dysfunction. Alternative explanations are discussed.
It has become an important task to develop a simple in vitro method for the detection of non-genotoxic carcinogens, among which tumor promoters are included. Bhas 42 cells are v-Ha-ras-transfected BALB/c 3T3 cells and are regarded as initiated cells in the 2-stage transformation paradigm. We designed a method for detecting tumor promoters by the use of Bhas 42 cells at advanced passage generation. In this method, the cells are cultured in six-well plates for 17 days during which test chemicals are added in the medium for 11 days from days 3 to 14. The end-point of the assay is the induction of transformed foci. When the tumor promoter TPA was used, a significant number of transformed foci were induced concentration-dependently, whereas only a few foci were observed in control cultures. When various chemicals were examined by the method, a reasonable correlation was observed with the reported tumor-promoting ability in animal experiments. We propose that the Bhas 42 cell transformation method is practical and useful for the detection of tumor promoters.
Optimized Si wire anodes have been prepared by macropore etching in p-Si and subsequent chemical/galvanic processing. The anodes have been optimized with respect to capacity, cycling performance and processing costs by fine-tuning the wire geometry. The optimized anodes have wires with ≈1μm in diameter and length of 70μm; they are as densely spaced as possible regarding volume expansion and electrolyte penetration requirements. A stable capacity of 3150mAh/g for 100 cycles has been reached during cycling to 75% of the maximum capacity. The operational range of the anodes is 0.11–0.7V. Optimal charging conditions were established by cyclic voltammetry measurements and battery cycling tests.
NMR spectroscopy continues to evolve, with publications in 2010 providing an eclectic collection of applications, advances and incremental improvements. A new 45 MHz NMR spectrometer was announced by PicoSpin: the world's first high-resolution NMR spectrometer that has the “foot-print” of a shoe-box. It is a programmable pulse-FT system that uses a permanent magnet and a flow-capillary sample delivery system. I am indebted to the great and the good whose work has been reported here, all credit is theirs; errors, omissions and blame are all mine.
Pacemaker implantation techniques using thoracoscopy have been described since about 25 years. However, the published reports concerning types of electrodes refer mostly to monopolar screw-in leads. We report our experience of thoracoscopic implantation of a bipolar suture-on epicardial electrode with monofilamentous sutures tightened by automated fasteners to avoid hand-tied knots.
The complexation of different simple anions (F−, Cl−, BF4 − and ClO4 −) with a neutral cryptand, with neutral BN dipoles as functional units, and modifications thereof has been studied using ab initio Hartree–Fock calculations. F− is the most strongly preferred anion for all cryptand versions, except for the largest cavity cryptand for which Cl− is preferred. The formed complexes in general show very low lithium ion affinities, much lower than those for anions such as PF6 − and TFSI (by up to 50%). The lowest lithium affinity is obtained for the combination of the smallest cryptand and the F− anion. Implications of using these cryptands in polymer electrolytes are discussed.
Objective This study examined the diagnostic value of the vestibular-evoked myogenic potential (VEMP) in comparison with the caloric test in patients with vestibular schwannoma (VS). Methods Data were retrospectively collected from 803 consecutive patients who visited our vertigo clinic and underwent vestibular tests. Amongst them, 78 patients were diagnosed as having untreated unilateral VS. VEMP was performed using click and short-tone burst stimulation. The caloric test was performed using ice water. The sensitivity and specificity of each test were evaluated. Results Of the 78 patients with VS, 63 had abnormal VEMPs as well as abnormal caloric responses. Of the 725 patients without VS, 382 had normal VEMPs and 416 had normal caloric responses. The sensitivity and specificity of VEMP were 80.8% (95% CI: 72.0–89.5%) and 52.7% (95% CI: 49.1–56.3%), respectively; those of the caloric test were 80.8% (95% CI: 72.0–89.5%) and 57.4% (95% CI: 53.8–61.0%), respectively. Conclusions The sensitivity and specificity of VEMP and the caloric test showed no significant differences. Significance In patients with VS, although the specificity of VEMP was not very high, its sensitivity was high and comparable to that of the caloric test.
This paper describes a prototype device to estimate the trajectory of the piston in a free-piston driver. The device, which screws to the front face of the piston, has an internal data acquisition system which triggers upon piston launch and records the acceleration history across the complete piston stroke. A key feature is the incorporation of an optical waypoint detector. This comprises a laser which is directed onto the compression tube wall, and a photodiode which measures the reflected intensity. A series of evenly spaced high-contrast lines are marked on the tube surface, which appear as a pattern of intensity changes in the photodiode signal and define a set of exact position–time coordinates along the trajectory. Optical pattern recognition has previously been shown to be effective to identify piston traversal past a fixed detector; in this application, the order is reversed so that the detector is on the piston, and the pattern is at the fixed location. Waypoint detection permits computation of a precise in situ calibration of the accelerometer and correction of the acceleration integration along the piston stroke. The key benefits of this concept are that it provides a complete, fully time-resolved, accurate estimate of piston position, is self-contained and portable, and can be readily utilised on any free-piston driver without significant modification to the facility.
Camphor vapour is pyrolysed in the presence of Fe, Ni and Co powder under a dinitrogen atmosphere at different temperatures (750–1050°C). While Fe and Ni catalyse the formation of carbon nanotubes (CNs), Co facilitates carbon nanobead growth. The CNs, obtained using a Fe catalyst at 950°C, are utilised as the anode in Li secondary batteries. The capacity of the batteries constructed in this way is as good as those prepared by graphitic carbon formed in the arc process.
In this experimental investigation, silicon nanoparticles and graphene nanosheets suspensions were produced by the pulsed laser ablation in distilled water separately. Then graphene and silicon were mixed in different volumetric ratio and irradiated by UV radiation to produced graphene/silicon nanocomposites. In order to characterize the structural and optical properties of samples, UV–Vis–NIR spectroscopy, Raman spectrum, and transmission electron microscopy were carried out. According to Raman spectra the defects introduced into the graphene nanosheets are more than the defects in the graphene/silicon nanocomposites. The extinction coefficients and bandgap energies of graphene/Si nanocomposites were decreased with increasing the amount of graphene suspension. The z-scan method was employed to estimate the role of the volume ratio of graphene nanosheets to silicon nanoparticles in changing the nonlinear responses of the graphene/silicon nanocomposites. Results of z-scan show that the nonlinear optical properties of graphene/silicon nanocomposites enhanced by increasing the concentration of Si nanoparticles. Furthermore, the measured values of third order nonlinear optical susceptibility,
Lithium-rich layered metal oxide electrode materials suffer from severe capacity fading and poor rate performance in lithium-ion batteries. Herein, we demonstrate that trimethylsilyl (trimethylsiloxy) acetate (bis-TMSA) can be used as a novel electrolyte additive to improve the electrochemical performance of Li1.2Ni0.2Mn0.6O2 cathode (LLC). The addition of 1% bis-TMSA in the electrolyte results in a large increase in the utilization efficiency of the electrode active material. Moreover, LLC in the bis-TMSA containing electrolyte can still deliver a discharge capacity of 136.97 mAh g−1 with capacity retention of 80.1% after 374 cycles at 1C, showing a superior cyclability. An enhancement in the rate capability of the material is also observed in the presence of bis-TMSA in the electrolyte. The effect of trace amount of water in the electrolyte on has been critical to the battery cycling performance. Removal of water in the electrolyte via hydrolysis of bis-TMSA leads to suppressed decomposition of electrolyte and less corrosion of electrode active material and current collector. Thinner SEI film with less F-containing species forms on the electrode surface and better contact between electrode material and current collector are responsible for the improved cyclability and rate capability for LLC in the bis-TMSA containing electrolyte.
Mg–Li, Mg–Li–Al and Mg–Li–Al–Ce alloys were prepared and their electrochemical behavior in 0.7M NaCl solutions was investigated by means of potentiodynamic polarization, potentiostatic current–time and electrochemical impedance spectroscopy measurements as well as by scanning electron microscopy examination. The effect of gallium oxide as an electrolyte additive on the potentiostatic discharge performance of these magnesium alloys was studied. The discharge activities and utilization efficiencies of these alloys increase in the order: Mg–Li<Mg–Li–Al<Mg–Li–Al–Ce, both in the absence and presence of Ga2O3. These alloys are more active than commercial magnesium alloy AZ31. The addition of Ga2O3 into NaCl electrolyte solution improved the discharging currents of the alloys by more than 4%, and enhanced the utilization efficiencies of the alloys by more than 6%. It also shortened the transition time for the discharge current to reach to a steady value. Electrochemical impedance spectroscopy measurements showed that the polarization resistance of the alloys decreases in the following order: Mg–Li>Mg–Li–Al>Mg–Li–Al–Ce. Mg–Li–Al–Ce exhibited the best performance in term of activity, utilization efficiency and activation time.
It has been demonstrated experimentally that a capacitor bank when connected in parallel with a battery increases the energy output by mitigating the effects of high current spikes in the load. High current draws are taken from the capacitor bank which can furnish a small amount of energy quickly. The battery which can furnish substantial energy over a period of time then recharges the capacitor bank during times of decreased load. With a current square wave (P–P of 1.5 to 2× the average), capacitors afforded an increase in the retrievable energy of approximately 8% for a lead acid battery, 40% for a rechargeable lithium ion battery, and 46% for a non-rechargeable lithium ion battery.
In this work, we synthesized radially developed metal oxides (MOs) array of one-dimensional (1D) nanostructured NiMoO4 on highly conductive carbon cloth (CC) and put forward an effective strategy to greatly improve the supercapacitor performance by enhancing the structural integrity and electrical oneness of the MO-based electrode. The hybrid NiMoO4/ polyaniline (PANI) electrode exhibits a high areal specific capacitance of ca. 1.34Fcm−2 (1340Fg−1) at a current density of 1mAcm−2. In comparison, the pristine NiMoO4 nanowires (NWs) have a specific capacitance of ca. 1.142Fcm−2 (1142Fg−1) at the same current density. An outstanding capacitance retention for NiMoO4/PANI hybrid nanowire electrodes has been achieved (ca. 96.7% after 2000 cycles with an average coulombic efficiency of over 99.5%), which is superior to pure NiMoO4 (ca. 81% after 2000 cycles). Moreover, a flexible all-solid-state asymmetric supercapacitor (ASC) employing NiMoO4/PANI and commercial active carbon (AC) as the positive and negative electrodes, respectively, delivers a maximum specific energy of 99.26 Wh Kg−1 (297.78 mWh cm−2) and a maximum specific power of 10667WKg−1 (32.04mWcm−2). In addition, the ASC device demonstrates highly stable cyclic performance with outstanding and robust flexibility.
Even though many forest villagers have been living on forest department land and serving the department in the northeastern hill forests region of Bangladesh since the early 1950s, their livelihood has not yet been fully explored. This paper examines the livelihoods of forest villagers (Khasia ethnic people) and their contribution to forest conservation, using data from the Sylhet forest division. The forest villagers are well-endowed with all the elements of a sustainable livelihoods framework, though human capital in terms of education is not satisfactory. Strong social capital, stable natural capital and a productive market-oriented agroforestry system facilitate the generation of financial and physical capital that make the livelihoods of Khasia people sustainable. At the same time, their reciprocal contributions in terms of forest protection and plantation development support forest conservation. However, some institutional issues such as insecure land tenure with regular agreement renewal problems need to be resolved for the sake of their livelihoods and forest conservation. Lessons learned from the study can be utilized in formulating future participatory forest management schemes in the country.
Reading skills at age 7–8 years were examined in a community-representative sample of 21 screened and clinically examined children with language delay (LD) followed prospectively from 2.5 years of age. The present study aimed to (1) determine whether these children with a history of LD had deficits in basic reading skills, i.e. decoding and comprehension, compared to the age norms of standardized tests, (2) analyze if there was a relationship between reading outcome and neuropsychiatric diagnosis by comparing three subgroups of children, LD pure, LD+ASD (autism spectrum disorder) and LD+ADHD, and, (3) determine what language measures at age 6 years were associated with the 7–8-year reading outcome. Both decoding and comprehension of single word reading were significantly below the norm for the whole LD group, where children with LD+ASD scored lowest, and children with LD highest. However, the differences between the three groups did not reach significance. Two reader groups were identified according to the results of word decoding and comprehension, respectively, resulting in the same 7 children. ANOVA revealed that the only differences on the 6-year language tests between the two groups were found on color naming and word memory. This study has shown that children with LD and subsequently identified neurodevelopmental problems such as ASD and ADHD experience continued deficits, demonstrated also in reading skills and that the picture of the reading problems seemed to resemble those of typically developing children.
The dynamic behavior of a proton exchange membrane fuel cell (PEMFC) system is a crucial factor to ensure the safe and effective operation of fuel cell hybrid vehicles (FCHVs). Specifically, water and thermal management are critical to stabilize the performance of the PEMFC during severe load changes. In the present study, the FCHV dynamic model is developed. The dynamic model of the PEMFC system developed by Matlab–Simulink® is integrated into the electric vehicle model embedded in the Amesim®. The dynamic model of the PEMFC system is composed of a PEMFC stack, an air feeding system, and a thermal management system (TMS). The component models of PEMFC, a shell-and-tube gas-to-gas membrane humidifier, and a heat exchanger are validated via a comparison with the experimental data. The FCHV model is simulated during a federal test procedure (FTP)-75 driving cycle. One system configuration and control strategy is adopted to attain optimal water and thermal management in the PEMFC system. The vehicle speed obtained from the FCHV model aptly tracks the target velocity profile of the FTP-75 cycle within an error of ±0.5%. The dynamic behavior and correlation of each component in the PEMFC system is investigated. The mass and heat transfer in the PEMFC, a humidifier, and a heat exchanger are resolved to determine the species concentration and the temperature more accurately with discretization in the flow’s perpendicular direction. Discretization in the flow parallel direction of humidifier and heat exchanger model makes it possible to capture the distribution of the characteristics. The present model can be used to attain the optimization of the system and control design for the PEMFC system in FCHVs.
Microgrid solutions can incorporate clean renewable energy and operate autonomously to power remote areas unreachable by the main grid. While microgrids have thus attracted the interest of many electricity operators, some suggest that renewable energy is not as environmentally friendly as it is claimed to be. This study investigates the life cycle environmental impacts and energy payback time (EPBT) of a microgrid through a life cycle assessment (LCA) case study of the Town Island Microgrid, the first standalone hybrid renewable energy commercial microgrid in Hong Kong. The environmental performance of the Town Island Microgrid was further tested against 2 electrification options, including an on-site diesel generator system and a grid extension. Our results indicate that the Town Island Microgrid is the least impactful in 8 impact categories out of 12. For instance, the global warming potential (GWP) of the diesel generator system and the grid extension was 4.3 times and 7.8 times greater than that caused by the microgrid, respectively. The EPBT for the microgrid was 9.2 years, while the grid extension and the diesel generator EPBT values were 6.4 and 10.1 times longer than that of the microgrid, respectively. In conclusion, the case study provides substantial evidence that a microgrid solution can deliver a significantly superior life cycle environmental performance than other common electrification options.
During the summers of 2003 and 2005, surface ozone concentrations were measured with portable ozone monitors at multiple locations in and around Yosemite National Park. The goal of these measurements was to obtain a comprehensive survey of ozone within Yosemite, which will help modelers predict and interpolate ozone concentrations in remote locations and complex terrain. The data from the portable monitors were combined with concurrent and historical data from two long-term monitoring stations located within the park (Turtleback Dome and Merced River) and previous investigations with passive samplers. The results indicate that most sites in Yosemite experience roughly similar ozone concentrations during well-mixed daytime periods, but dissimilar concentrations at night. Locations that are well exposed to the free troposphere during evening hours tend to experience higher (and more variable) nocturnal ozone concentrations, resulting in smaller diurnal variations and higher overall ozone exposures. Locations that are poorly exposed to the free troposphere during nocturnal periods tend to experience very low evening ozone, yielding larger diurnal variations and smaller overall exposures. Ozone concentrations are typically highest for the western and southern portions of the park and lower for the eastern and northern regions, with substantial spatial and temporal variability. Back-trajectory analyses suggest that air with high ozone concentrations at Yosemite often originates in the San Francisco Bay Area and progresses through the Central California Valley before entering the park.