batterydata/paper-abstracts huggingface dataset:
To evaluate ideal interfaces between Li metal and Li2S-P2S5 solid electrolytes, bulk-type cells were fabricated using thin Li metal films prepared by vacuum-evaporation. The symmetric cell of Li/75Li2S·25P2S5/Li showed a high utilization of Li metal (about 40%), though abrupt decrease of the utilization was observed after 5 cycles. A high utilization of Li metal (about 25%) was retained for 5 cycles by inserting Au thin films at the interface between Li metal and Li2S-P2S5 solid electrolytes. Morphology of Li metal after dissolution/deposition cycles for the cell with Au thin films became more uniform compared to the cell without Au thin films.
Tourette syndrome is a neurodevelopmental disorder characterized by multiple tics and is often associated with comorbid behavioral problems. Research with generic instruments in child populations showed that comorbid disorders can have a greater impact on health-related quality of life than tic severity. This study investigated the usefulness of a newly developed disease-specific instrument, the Gilles de la Tourette Syndrome–Quality of Life Scale for Children and Adolescents (GTS-QOL-C&A), in assessing health-related quality of life in young patients with Tourette syndrome with and without behavioral comorbidity. We recruited 75 patients with Tourette syndrome (60 males; age 12.4 ± 3.2 years). All participants were evaluated by a neuropsychiatrist and completed a standardized psychometric battery, including the GTS-QOL-C&A, Child Depression Inventory, and Multidimensional Anxiety Scale for Children. Forty-two patients (56%) fulfilled diagnostic criteria for at least one comorbidity: obsessive-compulsive disorder (n = 25 patients [33.3%]); attention deficit/hyperactivity disorder (n = 6 patients [8%]); both (n = 11 patients [14.7%]). The GTS-QOL-C&A demonstrated usefulness in differentiating “pure” Tourette syndrome from Tourette syndrome “plus” behavioral problems with regard to health-related quality of life scores for the obsessive-compulsive subscale. In addition to focusing on core tic symptoms, the GTS-QOL-C&A showed sensitivity to the impact of behavioral comorbidities on health-related quality of life and can usefully complement existing nonspecific instruments.
Polyacrylonitrile (PAN)/polyphenylsilane (PPS)-based composite carbon nanofibers (CCNFs) are prepared by one-step electrospinning and subsequent thermal treatment to produce organic-inorganic hybrid CCNFs. We investigate the electrochemical behavior and structural properties of these CCNF materials as a function the PAN/PPS ratio. The CCNFs show large specific surface area, high electrical conductivity and high thermal stability. In addition, the electrochemical performance of the organic–inorganic hybrid CCNF electrode is improved by the special porous structure and the silicon oxycarbide (Si–O–C)-related structure.
Background Short morning exposure to high illuminance visible electromagnetic radiations termed as artificial daylight is beneficial for the mental health of people living in geographical areas with important seasonal changes in daylight illuminance. However, the commercial success of high illuminance light sources has raised the question of the safety of long hour exposure. Methods We have investigated the effect of the replacement of natural daylight by artificial daylight in Swiss mice raised under natural lighting conditions. Mice were monitored for neurotoxicity and general health changes. They were submitted to a battery of conventional tests for mood, motor and cognitive functions’ assessment on exposure day (ED) 14 and ED20. Following sacrifice on ED21 due to marked signs of neurotoxicity, the expression of markers of inflammation and apoptosis was assessed in the entorhinal cortex and neurons were estimated in the hippocampal formation. Results Signs of severe cognitive and motor impairments, mood disorders, and hepatotoxicity were observed in animals exposed to artificial daylight on ED20, unlike on ED14 and unlike groups exposed to natural daylight or conventional lighting. Activated microglia and astrocytes were observed in the entorhinal cortex, as well as dead and dying neurons. Neuronal counts revealed massive neuronal loss in the hippocampal formation. Conclusions These results suggest that long hour exposure to high illuminance visible electromagnetic radiations induced severe alterations in brain function and general health in mice partly mediated by damages to the neocortex-entorhinal cortex-hippocampus axis. These findings raise caution over long hour use of high illuminance artificial light.
Countries are investing in renewable energy such as wind or solar to meet electricity demand and minimize CO2 emissions. Due to the intermittent nature of these energy sources, back-up generating assets or adequate storage is needed to meet peak demand. In this study, we evaluate the extent to which an electricity grid can rely on intermittent renewable energy (wind and solar) if a ‘black box’ battery is used for storage. We examine the potential for 100% generation from wind and solar, as well as scenarios that are consistent with a policy to eliminate coal generation. A constrained optimization model is used that minimizes thermal generating capacity and battery size subject to load and battery constraints. Our application is to the fossil-fuel dependent Alberta electricity system. Our results suggest that it might be difficult and costly to supply the grid with 100% renewable energy. Replacing coal with renewable energy and using natural gas and a battery as back-up would be feasible, but would require a very large battery and result in high costs. Other storage methods should be considered to facilitate increased generation from renewable sources.
Four designs of flow fields were applied to micro-proton exchange membrane fuel cells (μ-PEMFCs) using microelectromechanical system (MEMS) technology. The flow fields and membrane electrolyte assembly (MEA) of 2.25cm2 active area were assembled to μ-PEMFCs. Electrochemical behaviors of these μ-PEMFCs were investigated by polarization method at reactants flow rates of 15mlmin−1, 30mlmin−1 and 50mlmin−1, respectively. This study emphasized the effects of different topologies of flow fields on performance of μ-PEMFCs. Results demonstrated that μ-PEMFCs with different flow fields have similar behavior at reactants flow rates of 50mlmin−1. However, at reactants flow rates of 15mlmin−1 and 30mlmin−1, performance of the μ-PEMFC with long and narrow micro-channels rapidly deteriorated due to the flooding in micro-channels. The mixed serpentine design had a good ability to resist the flooding, but it displayed a low maximum power density because of its short effective length of micro-channels. The results in this study suggested that the μ-PEMFC with a mixed multichannel design flow field and long micro-channels yielded the best performance.
LiNi0.5Mn1.5O4 spinel has been prepared by an emulsion drying method which can intermix cations very homogeneously at the atomic scale. When the emulsion-dried precursor was fired at 750°C for 24 h, the observed particle of the LiNi0.5Mn1.5O4 was nano-crystallite, being about 50 nm in diameter. The Rietveld refinement result clearly exhibited that the cubic spinel phase was successfully formed without any secondary phases, indicating that Li and transition metal cations occupied the 8a and 16d sites of the Fd3m structure, respectively. Li deintercalation from the spinel framework brings about a shift in the XRD peak toward higher angles and a peak splitting in the composition range δ=0–0.2 in Li δ Ni0.5Mn1.5O4, implying that the host structure is progressively oxidized from Ni2+ to Ni4+ and accompanied by a two phase reaction. The sample calcined at 750°C for 24 h showed the best cyclability upon cycling due probably to better crystallinity and a smaller particle size. We suggest that this material can be used as a 4.5 V cathode material for Li-ion battery.
The study examined the influence of psycho-social factors on youths’ attitude towards Internet fraud in Nigeria. Opinions of two hundred undergraduate students of Department of Computer Science, Benue State University, Makurdi were randomly sampled for this study. A battery of test such as Big-Five Personality Inventory, Need Achievement Questionnaire, and Attitude towards Internet Fraud Questionnaire were administered to the students. It was found out that sex, age, need for achievement, psychoticism, neuroticism and extraversion were significantly, independently and jointly predicted youths’ attitude towards Internet fraud {F (6, 199)=55.52, p<.01, Adjusted R2 =.622}. It was also found out that sex (β =0.134, t=2.317, p<.05) and need for achievement (β =0.702, t =12.183, p<.05) had significant, independent prediction on youths’ attitude towards Internet fraud in Benue State, Nigeria. It was thus recommended that Africans should re-examine their value system; the child needs to be oriented towards his culture right from birth. The adopted curriculum of Western Education should be modified or adapted. More beneficial aspect of African culture should be introduced in the formal school system. Our yardstick for measuring affluence has to be changed to discourage our youths from exchange of money or gift for sex or prostitution. The implications of the study were discussed.
Lithium-sulfur (Li-S) batteries belong to one of the promising technologies for high-energy-density rechargeable batteries. However, sulfur cathodes suffer from inherent problems of its poor electronic conductivity and the shuttling of highly dissoluble lithium polysulfides generated during the cycles. Loading sulfur into porous carbons has been proved to be an effective approach to alleviate these issues. Mesoporous and microporous carbons have been widely used for sulfur accommodation, but mesoporous carbons have poor sulfur confinement, whereas microporous carbons are impeded by low sulfur loading rates. Here, a core-shell carbon, combining both the merits of mesoporous carbon with large pore volume and microporous carbon with effective sulfur confinement, was prepared by coating the mesoporous CMK-3 with a microporous carbon (MPC) shell and served as the carbon host (CMK-3@MPC) to accommodate sulfur. After sulfur infusion, the as-obtained S/(CMK-3@MPC) cathode delivered a high initial capacity of up to 1422 mAh·g−1 and sustained 654 niAh·g−1 reversible specific capacity after 36 cycles at 0.1 C. The good performance is ascribed to the unique core-shell structure of the CMK-3@MPC matrix, in which sulfur can be effectively confined within the meso/microporous carbon host, thus achieving simultaneously high electrochemical utilization.
Li2TiSiO5 presents an operational potential at 0.28 V vs. Li+/Li, which could fill the voltage gap between graphite and Li4Ti5O12, showing great potential as an alternative anode material for Li-ion batteries. Apart from its advantages such as proper operational potential, excellent reversibility, low cost, environment friendly and so on, Li2TiSiO5 also suffers from two shortages of relatively low rate performance and capacity-voltage curve changing during cycling. In this work, we introduced expanded graphite as supporting medium, and successfully synthesized Li2TiSiO5 nanoparticles loaded expanded graphite composites (LTSO-EG). By dramatically reducing particle size and improving electronic conducting material, the rate performance of LTSO-EG is greatly improved compared with the amorphous carbon coated Li2TiSiO5. And most importantly, LTSO-EG displays a slope and stable capacity-voltage curve during cycling with reduced polarization.
Zr-doped LiNi0.5Mn1.5O4-δ (Zr-LNMO) is synthesized by a solid-state method and the effects of Zr-doping on its structural behavior are systematically investigated by using synchrotron-based in situ x-ray diffraction during the 1st and the 2nd cycles between 1.0 and 5.0 V. Differences in the structural changes for Zr-LNMO and LNMO during cycling were clearly observed. Both samples show similar reversible phase transitions between three cubic phases and two tetragonal phases during the 1st cycle. However, during the 2nd cycle, overall phase transitions between tetragonal and cubic phases for Zr-LNMO show more reversible features than those for LNMO. In situ XRD results during the 2nd cycle reveal that some parts of LNMO cathode materials do not contribute to the capacity, due to the incomplete phase transition between cubic and tetragonal phases and sluggish phase transition kinetics. It is proposed that the increase in the lattice volume by Zr-doping allows more reversible structural changes during repeated cycling, compared to the undoped LNMO, resulting in the improved capacity retention of Zr-LNMO. This study shows that Zr-doping has a great potential, if optimized, to provide structural stability during repeated cycling, thereby leading to superior cycling stability.
Effects of methanol, ethanol, 2-propanol and water on the proton conductivity and surface properties of Nafion membrane have been studied by electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM). It was established that both conductivity and surface topography decrease in alcohol environment while they show high values and big roughness when Nafion is in aqueous environment. We have measured the conductivity of Nafion in water–alcohol mixtures environments and results give evidence of conductivity and dielectric constant dependence, which has been explained on the basis of Born and Arrhenius equations. Nafion's surface properties were investigated by contact and tapping AFM modes. Surface topography considerably changes when samples absorb water. However, samples stored in alcohols are characterized by flat surfaces. Surface modification was linked to an expansion phenomenon during the swelling of Nafion by solvents. Tapping mode phase images showed that ionic and cluster domains are distinguishable from the surface of samples impregnated either in water or alcohols.
This work focuses on developing a new adsorptive material and regenerable system for CO2 sequestration to supply CO2-free gas stream for low temperature and low carbon dioxide concentration applications, such as alkaline fuel cells, metal-air batteries, and portable air-purifying respirators. A novel microfibrous media has been introduced for carbon dioxide filtration from wet gas streams at room temperature. The use of microfibrous media in a composite bed maximizes the breakthrough capacity per unit volume and promotes high accessibility. The microfibrous media synergically combines the high contacting efficiency of the microfibrous matrix and the small internal mass transfer resistance of small particulates. The carbon dioxide adsorption capacity of the microfibrous media can be reversibly recovered. The incorporation of microfibrous media to the sodalime was observed. The result shows 120% improvement in the breakthrough capacity compared with the packed bed of the sodalime with the same volume. This approach can be applied to miniaturize the reactor and reduce thermal mass enhancing process intensification.
Three-dimensional tin thin-film anode was prepared by electroless plating tin onto three-dimensional (3D) copper foam (which served as current collector), and characterized physically by SEM, EDS and XRD. Its electrochemical property and mechanism were studied by charge–discharge test, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The SEM and EDS results indicated that tin film with 500nm thickness was formed over the whole surface of copper branches. The XRD results suggested that a new phase of Cu6Sn5 was formed between copper and tin. Besides the tin microflake structure of 500nm thickness, the interaction effects of the copper foam and Cu6Sn5 phase formed between copper and tin resulted in good cycle performance with first discharge capacity of 737mAhg−1, 97% capacity retention after 20 cycles and still 84% after 40 cycles.
The antithyroid acting drug propylthiouracil (PTU) was administered to male and female Wistar rats at 0, 0.1, 1, or 10mg/kg body weight for 4 weeks according to the draft protocol of the “Enhanced OECD Test Guideline 407” (enhanced TG 407) in order to investigate its suitability to detect endocrine-mediated effects. The study was conducted with two identical subsets of five animals per sex and dose each to provide data on sensitivity. The modified protocol includes the investigation of additional organ weights, pathology, and histopathology, of thyroid hormones, of spermatozoa, and of estrus cycle. At time of sacrifice, all females were in the diestrus stage as prescribed. Adverse effects were observed in the thyroid gland (hypertrophy/ hyperplasia) and the pituitary gland (hyperplasia of basophilic cells, hypoplasia of acidophilic cells) together with dose-related decreased serum triiodothyronine (T3) and thyroxine (T4) levels and increased thyroid stimulating hormone (TSH) levels. Other effects of PTU included decrease of organ weights, anaemia, impaired blood coagulation, and reduced activity of enzymes. Hence, some of the additional examined endpoints of the enhanced TG 407, e.g., examination of pituitary gland and thyroid hormones, were suitable to detect endocrine-modulating effects of propylthiouracil. Treatment of five animals provides sufficient sensitivity to detect the described adverse effects of propylthiouracil. The enhanced TG is currently under investigation in several laboratories, evaluation of all the results will allow determining its practicability as well as the most suitable additional endpoints.
The development of highly efficient and bifunctional electrocatalysts is highly desirable for commercializing the rechargeable Zn-air battery. Herein, employing graphitic carbon nitride as carbon precursor, N-doped carbon sheets loaded with Ni3Fe nanoparticles (denoted as Ni3Fe/N-C) have been prepared via a simple pyrolysis strategy. Benefitting from the introduction of triethylene diamine as organic ligand, Ni3Fe nanoparticles with a mean size of 29 nm are dispersed on NC sheets uniformly. As a result, Ni3Fe/N-C exhibits excellent electrocatalytic activity toward both oxygen reduction and evolution reactions (For oxygen reduction reaction, the half-wave potential of Ni3Fe/N-C is 0.81 V; for oxygen evolution reaction, the overpotential at 10 mA cm− 2 is 310 mV). Finally, when used as air electrode in rechargeable Zn-air battery, a high power density of 128 mW cm− 2 and a long cycling life up to 134 h at 10 mA cm− 2 are achieved. Our study thus provides a promising air electrode material for rechargeable Zn-air batteries.
Microbial bioelectrochemical systems (BESs) interconvert electrical and chemical energy, enabling electricity generation, hydrogen production, chemical synthesis, wastewater treatment, desalination, and remediation. The focus of this review is design of bioelectrodes for BESs. Desirable features are high conductivity, stability, and biocompatibility. We trace the history of bioelectrode design from nonporous designs to modern porous designs that are particle-based, fiber-based, or monolithic, and compare performance characteristics. The most promising strategies use porous structures conducive to microbial colonization and surface materials that promote efficient electron transfer.
Solid polymer electrolytes are considered promising candidates for application in Li-metal batteries due to their comparatively high mechanical strength, which can prevent dendrite formation. In this study, we have performed Molecular Dynamics simulations to investigate structural and dynamical properties of a common polymer electrolyte, poly(ethylene oxide) (PEO) doped with LiTFSI salt in the presence of a Li metal surface. Both a physical (solid wall) and a chemical (slab) model of the Li (100) surface have been applied, and the results are also compared with a model of the bulk electrolyte. The average coordination numbers for oxygen atoms around the Li ions are ca. 6 for all investigated systems. However, the calculated Radial Distribution Functions (RDFs) for Li+-OPEO and Li+-OTFSI show sharper peaks for the Li slab model, indicating a more well-defined coordination sphere for Li+ in this system. This is clearly a surface effect, since the RDF for Li+ in the interface region exhibits sharper peaks than in the bulk region of the same system. The simulations also display a high accumulation of TFSI anions and Li+ cations close to interface regions. This also leads to slower dynamics of the ionic transport in the systems, which have a Li-metal surface present, as seen from the calculated mean-square-displacement functions. The accumulation of ions close to the surface is thus likely to induce a polarization close to the electrode.
Using the Child Behavior Checklist, the behavior of 16 children with cryptogenic localization-related epilepsy was assessed at first admission to our epilepsy center, and approximately 2 years later. Behavior improved substantially from t1 (first assessment, when patients were admitted to our center) to t2 (reassessment after approximately 2 years) on almost all subscales of the Child Behavior Checklist. At t2, all subscales scored within normal range. Furthermore, seizure frequency improved considerably in the 2 years between assessments. After a period of approximately 2 years, normalization of behavior in children with cryptogenic localization-related epilepsy occurred.
Here, we report a one-step simultaneous-construction approach to synthesize N-doped carbon@MoSe2 core/branch nanostructures by heating a mixture of MoO3/PANI hybrids and Se powders in argon atmosphere, without requiring a cumbersome multi-step process or highly toxic reducing agents. It is found that in the construction process, PANI played a crucial role in the reduction of MoO3 and Se to form MoSe2 nanosheet branches, while PANI itself was decomposed and carbonized into N-doped carbon nanorod cores. Interestingly, the coexistence of 1D and 2D nanostructures in the N-doped carbon@MoSe2 core/branch system leads to excellent lithium storage performance, including a large discharging capacity of 1275mAhg−1, a high reversible lithium extraction capacity of 928mAhg−1 and a coulombic efficiency of 72.8%. After 100 cycles, the NDC@MS electrode still delivers a reversible capacity of 906mAhg−1 with a capacity retention ratio of 97.6%. The superior electrochemical properties can be attributed to the unique core/branch nanostructure of NDC@MS and the synergistic effect between the N-doped carbon nanorod cores and MoSe2 nanosheet branches.
Many students enroll in less selective colleges than they are qualified to attend, despite low graduation rates at these institutions. Some scholars have argued that qualified students should enroll in the most selective colleges because they have greater resources to support student success. However, selective college attendance is endogenous, so student outcomes could be due to individual ability, not institutional characteristics. Previous work on college selectivity has focused on the earnings effects of attending elite private universities, overlooking both college graduation impacts and the public institutions that educate most students. I estimate the effect of selective colleges on the probability of bachelor’s degree completion using a restricted-access national dataset and an instrumental variables approach to address the endogeneity of college choice. I find that a 100-point increase in the average SAT score for admitted students is associated with an increase in the probability of graduation by 13 percentage points. In addition, I find suggestive evidence that enrolling in a selective public college has a positive effect on degree completion. The results are robust to a series of sensitivity tests and alternate specifications. The findings suggest strong benefits to enrolling in the most selective colleges that students are qualified to attend and have important implications for decisions to pursue postsecondary education in the face of high student loan debt.