batterydata/paper-abstracts huggingface dataset:
Room-temperature sodium–sulfur (RT-Na–S) batteries are highly desirable for grid-scale stationary energy storage due to their low cost; however, short cycling stability caused by the incomplete conversion of sodium polysulfides is a major issue for their application. Herein, we introduce an effective sulfiphilic host, gold nanodots decorated on hierarchical N-doped carbon microspheres (CN/Au/S), to achieve completely reversible conversion reactions in the S cathode by electrocatalyzing the low-kinetics conversion of Na2S4 into NaS2 (discharge process) or S (charge process). Besides, gold nanodots and N-doped carbon can increase the conductivity of the S cathode and provide strong polar–polar adsorption of sodium polysulfides to alleviate the shuttling effects. When serving as the cathode, the CN/Au/S composite can realize enhanced sulfur utilization, excellent cycling stability, and outstanding rate capability. This work deepens our understanding of the catalytic effect of gold atoms on sulfur molecules, opening a new avenue for cathode design and development of advanced RT-Na–S batteries.
Today, special interest is focused on polymer systems showing high ionic conductivity at ambient and/or sub ambient temperatures, since they find unique practical applications, such as separators in high power, versatile, rechargeable Li-based batteries. Thermo-set membranes prepared by free radical photo polymerisation (UV-curing) could be an interesting alternative to existing polymer electrolytes. In the present paper, we report the application of this technique to the synthesis of gel-polymer membranes which can be used as electrolytes for lithium battery application. These membranes are prepared by mixing a dimethacrylic (BEMA) and/or a diacrylic monomer (PEGDA), a methacrylic reactive diluent (PEGMA) and a radical photo-initiator with the in situ addition of a EC/DEC solution. The above mixtures are UV irradiated to obtain transparent, flexible, easy to handle gel-polymer films. The gel-polymer electrolytes (GPEs) are then prepared by swelling these membranes in different liquid electrolytes. The results obtained indicate some superior and satisfactory performances in terms of ionic conductivity at ambient temperature for various GPEs prepared with different lithium salt solutions. The relevance of these features in view of practical application is here demonstrated by the response of lithium cells based on prepared GPEs.
A novel polyvinyl alcohol (PVA) hydrogel method is developed to synthesize Si/CNT/C composites. The Si nanoparticles and CNTs are ‘position’ locked up by PVA hydrogel in a simple aqueous solution process, and then the Si-CNT-PVA hydrogel has pyrolyzed to form Si/CNT/C composites. In this unique structured Si/CNT/C composites, the CNTs form a porous network acting both as conductive agent for electron transfer and buffer space to accommodate huge Si volume change during lithiation/delithiation process, while the coating layer of carbon carbonized from polyvinyl alcohol (PVA) hydrogel is conducive to stabilize the interweaved composite structure. The complex structures of Si/CNT/C composites and their electrochemical properties are presented in this paper. The Si/CNT/C composites exhibit an initial reversible capacity of nearly 800 mAhg−1, an excellent capacity retention of 97.1% after 100 cycles at the rate of 0.1 C, and high capacity retention even at high current rate.
Honeycomb porous MnO2 nanofibers (HMONFs) have been prepared by solution reaction between KMnO4 and electrospun carbon nanofibers (CNFs). The HMONFs are entirely composed of radially grown MnO2 nanosheets with thickness about 3–7nm, which interconnect each other, forming the honeycomb pores. Formation of this unique structure occurs only at very low KMnO4 concentrations and sufficiently long reaction time. The constituting MnO2 nanosheets in the HMONFs are well separated with the sheet edges oriented on the surface, leading to excellent supercapacitive performance. Symmetric aqueous supercapacitors are assembled using the HMONFs and 1M Na2SO4 electrolyte, which exhibits a working voltage as high as 2.2V and high energy density of 41.1Wh/kg at the power density of 3.3kW/kg. The supercapacitor capacity can be retained about 76% of its initial value after 3500 cycles, which is acceptable due to its high energy density. These results indicate that the HMONFs are of high promise in developing advanced supercapacitors with high working voltage and energy density for practical applications.
A direct deposition technique based on electrophoresis is employed to prepare positive electrode for Li-ion batteries. Li[Ni1/3Co1/3Mn1/3]O2 (active material), denka black (conductive agent) and PVDF (binder) is dispersed in the solvent and used as a suspension for electrophoretic deposition (EPD) process. The Box-Bhenken design is made to optimize the EPD suspension, by varying three controllable input factors namely weight of active material, conductive agent and binder. The output responses are initial discharge capacity and capacity retention ratio. There is a good agreement between the actual and predicted values. The adequacies of the models are established with analysis of variance. The response surface methodology with desirability function is used to determine the optimum deposition condition to obtain maximum initial discharge capacity and capacity retention ratio for the EPD prepared positive electrode. The developed design predicts the 500mg of active material, 10mg of conductive agent and 30mg of binder as an optimum condition for maximum discharge capacity of 152mAh/g and capacity retention ratio of 93%. For confirmation, the electrode prepared with these optimum parameters gives discharge capacity of 147.18mAh/g and capacity retention ratio of 97.11%. EPD process is suggested to be efficient for fabrication of positive electrode under the predicted optimal condition in accordance to the positive electrode prepared by Doctor blade method.
In this study, a conversion coating was deposited on the surface of aluminum (Al) foil used as the packaging foil of lithium ion battery by immersion in cerium (Ce) conversion solution modified with or without γ-(methacryloxypropyl) trimethoxy silane (KH570). The morphology, composition and wettability of the conversion coating were investigated by scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy and contact angle measurement. In addition, a six-layered packaging film was prepared by hot pressing using casting polypropylene as the inner layer and maleic anhydride grafted polypropylene (PP-g-MAH) as the inner adhesive. The adhesion and heat-sealing properties of untreated, Ce treated and KH570 modified Ce treated (KH570-Ce) Al foils were characterized by T-peeling test. The results show that a homogeneous and hydrophobic coating is formed on the surface of KH570-Ce treated Al foil, and the adhesion between the inner adhesive and the KH570-Ce treated Al foil substrate is greatly improved because of the synergistic effect of silane and Ce-containing conversion coating.
A sulfur/graphene composite is prepared by loading elemental sulfur into three-dimensional graphene (3D graphene), which is assembled using a metal ions assisted hydrothermal method. When used as cathode materials for lithium–sulfur (Li–S) batteries, the sulfur/graphene composite (S@3D-graphene) with 73 wt % sulfur shows a significantly enhanced cycling performance (>700 mAh g−1 after 100 cycles at 0.1C rate with a Coulombic efficiency > 96%) as well as high rate capability with a capacity up to 500 mAh g−1 at 2C rate (3.35 A g−1). The superior electrochemical performance could be attributed to the highly porous structure of three-dimensional graphene that not only enables stable and continue pathway for rapid electron and ion transportation, but also restrain soluble polysulfides and suppress the “shuttle effect”. Moreover, the robust structure of 3D graphene can keep cathode integrity and accommodate the volume change during high-rate charge/discharge processes, making it a promising candidate as cathode for high performance Li–S batteries.
The economic production of wearable energy storage devices exhibiting mechanically-compliable form factors and reliable performance enable exciting opportunities in emerging technologies of consumer electronics, human-machine interface, and the Internet of Things. Here we report a hybrid scheme for designing and nanomanufacturing ultralight, high-performance supercapacitor electrodes through the hydrothermal growth of two-dimensional MnO2 on three-dimensional printed graphene aerogel (GA). The derived mixed-dimensional hierarchical macroporous composite electrodes exhibit superior specific capacitance and excellent cycling stability after thousands of cycles. We further explored the integration of a contact mode triboelectric nanogenerator and a mixed-dimensional MnO2/GA based supercapacitor into a self-powered system that is capable of converting mechanical signals into electrical power and further storing such scavenged power. The holistic integration of energy harvesting and storage units promises the implementation of self-powered wearable devices with greater intelligence that can scavenge and store environmental energy through sustainable pathways for ubiquitous electronics in societally-pervasive applications.
Heart failure remains the leading cause of death in Western countries, affecting 4.9 million individuals and causing >300 000 deaths annually in the US alone. The disease is highly prevalent in the elderly population and often follows a course of progressive disability and deterioration. An estimated 15 000 patients with end-stage heart failure could benefit from heart transplant each year. Yet, as a result of a significant shortage of donor organs, only 2500 hearts are donated annually, and approximately one-third of patients awaiting heart transplant die each year. Mechanical circulatory support, primarily in the form of left ventricular assist devices (LVADs), has come to the forefront of treatment for severe congestive heart failure by providing a feasible alternative to patients who might otherwise die awaiting heart transplant. The arrival of LVADs has resulted in a dramatic shift in the management of heart failure, one that will undoubtedly affect and include a vast proportion of elderly patients. While LVADs represent a surgical approach to a disease that has traditionally been managed medically, the pharmacological application throughout the perioperative period remains of critical importance.
Stand alone photovoltaic (PV) systems comprise one of the promising electrification solutions to cover the demand of remote consumers, especially when it is coupled with a storage solution that would both increase the productivity of power plants and reduce the areas dedicated to energy production. This short communication presents a multi-objective design of a remote PV system coupled to battery and hydrogen storages systems simultaneously minimizing the total levelized cost and the occupied area, while fulfilling a constraint of consumer satisfaction. For this task, a multi-objective code based on particle swarm optimization has been used to find the best combination of different energy devices. Both short and mid terms based on forecasts assumptions have been investigated. An application for the site of La Nouvelle in the French overseas island of La Réunion is proposed. It points up a strong cost advantage by using Heterojunction with Intrinsic Thin layer (HIT) rather than crystalline silicon (c-Si) cells for the short term. However, the discrimination between these two PV cell technologies is less obvious for the mid term: a strong constraint on the occupied area will promote HIT, whereas a strong constraint on the cost will promote c-Si.
Using a one-pot approach based on solvothermal reactions, we have successfully constructed nanoarchitectures consisting of MnOOH nanorods and reduced graphene oxide (RGO) - MnOOH@RGO without adding any surfactant. The nanocomposites show highly enhanced speciﬁc capacitance of 268F·g−1 at a current density of 0.5A·g−1, compared to pure MnOOH (108F·g−1). The asymmetric supercapacitors made with MnOOH@RGO nanoarchitectures and activated carbon (AC) exhibit excellent performances in energy storage. The devices can achieve a maximum energy density of 41.1Wh·kg−1 at power density of 400W·kg−1, and a maximum power density of 12.8kW·kg−1 at energy density of 10.7Wh·kg−1, based on the total mass of active materials. They also demonstrate excellent cycling durability retaining 98.3% of specific capacitance even after cycling for 5000 times. The highly enhanced capacity in energy storage of the nanoarchitectures could be attributed to high density of MnOOH nanorods with well controlled nanostructure loaded onto the surface of RGO in the one-pot synthesis and therefore dramatically improved conductivity of the nanoarchitectures in the presence of percolated graphene nanosheets.
Proliferation assays based on human cell lines are the most used in vitro tests to determine estrogenic properties of compounds. Our objective was to characterise to what extent these in vitro tests provide alternatives for the in vivo Allen and Doisy test, a uterotrophic assay in immature or ovariectomised rodents with uterus weight as a crucial read-out parameter. In the present study four different human cell lines derived from three different female estrogen-sensitive tissues, i.e. breast (MCF-7/BOS and T47D), endometrial (ECC-1) and ovarian (BG-1) cells, were characterised by investigating their relative ERα and ERβ amounts, as the ERα/ERβ ratio is a dominant factor determining their estrogen-dependent proliferative responses. All four cell lines clearly expressed the ERα type and a very low but detectable amount of ERβ on both the mRNA and protein level, with the T47D cell line expressing the highest level of the ERβ type. Subsequently, a set of reference compounds representing different modes of estrogen action and estrogenic potency were used to investigate the proliferative response in the four cell lines, to determine which cell line most accurately predicts the effect observed in vivo. All four cell lines revealed a reasonable to good correlation with the in vivo uterotrophic effect, with the correlation being highest for the MCF-7/BOS cell line (R 2 =0.85). The main differences between the in vivo uterotrophic assay and the in vitro proliferation assays were observed for tamoxifen and testosterone. The proliferative response of the MCF-7/BOS cells to testosterone was partially caused by its conversion to estradiol by aromatase or via androstenedione to estrone. It is concluded that of the four cell lines tested, the best assay to include in an integrated testing strategy for replacement of the in vivo uterotrophic assay is the human MCF-7/BOS breast cancer cell line.
We report the synthesis and characterization of a novel class of ionic semiconductor materials – inorganic chalcogenide perovskites. Several different compounds including BaZrS3, CaZrS3, SrTiS3 and SrZrS3 were synthesized by high temperature sulfurization of their oxide counterparts. Their crystal structures were identified by XRD and composition by EDX. UV–vis and photoluminescence measurements confirmed that they are direct gap semiconductors with band gap values consistent with theoretical predictions. By adopting an anion alloying approach, we demonstrate widely tunable band gap from 1.73eV to 2.87eV. These strongly ionic semiconductors provide a new avenue for engineering the semiconducting properties for applications such as energy harvesting, solid state lighting and sensing.
Analysis of 89 biallelic polymorphisms in 523 Turkish Y chromosomes revealed 52 distinct haplotypes with considerable haplogroup substructure, as exemplified by their respective levels of accumulated diversity at ten short tandem repeat (STR) loci. The major components (haplogroups E3b, G, J, I, L, N, K2, and R1; 94.1%) are shared with European and neighboring Near Eastern populations and contrast with only a minor share of haplogroups related to Central Asian (C, Q and O; 3.4%), Indian (H, R2; 1.5%) and African (A, E3*, E3a; 1%) affinity. The expansion times for 20 haplogroup assemblages was estimated from associated STR diversity. This comprehensive characterization of Y-chromosome heritage addresses many multifaceted aspects of Anatolian prehistory, including: (1) the most frequent haplogroup, J, splits into two sub-clades, one of which (J2) shows decreasing variances with increasing latitude, compatible with a northward expansion; (2) haplogroups G1 and L show affinities with south Caucasus populations in their geographic distribution as well as STR motifs; (3) frequency of haplogroup I, which originated in Europe, declines with increasing longitude, indicating gene flow arriving from Europe; (4) conversely, haplogroup G2 radiates towards Europe; (5) haplogroup E3b3 displays a latitudinal correlation with decreasing frequency northward; (6) haplogroup R1b3 emanates from Turkey towards Southeast Europe and Caucasia and; (7) high resolution SNP analysis provides evidence of a detectable yet weak signal (<9%) of recent paternal gene flow from Central Asia. The variety of Turkish haplotypes is witness to Turkey being both an important source and recipient of gene flow.
There has been increasing evidence that ether-based electrolytes offer more stable anode performance in sodium ion batteries, even for microsized alloy electrodes which suffer huge volume change upon charge/discharge cycling. It is speculated that ether-based electrolytes may give rise to more robust solid electrolyte interphases (SEIs), but the detailed mechanism remains unknown, due to the structural complexity and the extremely vulnerable nature of SEIs. In this work, we unveil the characteristic SEI structure at Sn electrode surfaces in both carbonate- and ether-based electrolytes. We adopt cryogenic transmission electron microscopy to probe the pristine SEI structure, in combination with X-ray photoelectron spectroscopy and density functional theory calculations. An ultrathin SEI forms in the ether-based electrolyte, with amorphous particles dispersed in the polymer-like matrix. This unique nanostructure exhibits superior mechanical elasticity and renders anomalous stability against the large volume change of alloy electrodes, as evidenced by both electrochemistry measurement and atomic force microscopy. Our work unravels the causes for the superiority of ether-based electrolytes in sodium-ion batteries, and we expect the potential of such an optimized SEI to enable the application of high-capacity anodes such as microsized alloys.
Nunavik is a subarctic remote region covering the northern third of Québec, Canada, where low efficiency and environmentally adverse diesel furnaces are currently used to meet residential heating demand. Studies focusing on building heating alternatives in subarctic climate are limited and hence, this work can help with the development of such systems in remote off-grid communities. Shallow geothermal potential was mapped for Kuujjuaq, the largest village in Nunavik. Four ground-coupled heat pump scenarios were analysed for a simulated 5-occupant residential dwelling, with heating needs of 71 MWh/year. Resulting maps show a relatively high ground potential for such cold region, ranging between 5.8 MWh/year and 22.9 MWh/year per borehole for heat exchanger lengths of 100 m–300 m. A 50-year life-cycle cost analysis of such systems reveal that a compression heat pump with electricity derived from solar photovoltaic panels has a net present cost as low as approximately CAD$179,000, representing the most economically attractive heating option in Kuujjuaq as compared to the currently subsidized, diesel furnace heating at CAD$277,000. This work verifies that shallow geothermal energy through state-of-the-art heat pumps is a financially interesting option in Kuujjuaq. Results can be extended to similar subarctic settings in Canada and worldwide.
Tin oxide (SnO2) is a promising candidate as an anode for lithium ion batteries because of its high theoretical capacity. However, poor capacity retention caused by large volume changes during cycling, large initial irreversible capacity, and low rate capability frustrate its practical application. We have developed a ternary nanocomposite based on tin indium oxide (SnO2–In2O3) and graphene nanosheet (GNS) synthesized via a facile solvothermal method. The incorporation of In2O3 into SnO2 can improve the electrochemical property of SnO2 and reduce the charge transfer resistance of electrode leading to the enhanced reversible capacity and rate capability. The graphene nanosheet in the composite electrode can accommodate high volume expansion/contraction during cycling resulting in excellent capacity retention. As an anode for lithium ion batteries, the SnO2–In2O3/GNS nanocomposite exhibits a remarkably improved electrochemical performance in terms of lithium storage capacity (962mAhg−1 at 60mAg−1 rate), initial coulombic efficiency (57.2%), cycling stability (60.8% capacity retention after 50 cycles), and rate capability (393.25mAhg−1 at 600mAg−1 rate after 25 cycles) compared to SnO2/GNS and pure SnO2–In2O3 electrode.
KxCu1−xO1−γ (0 ≤ x ≤ 0.12) and K0.08Cu0.92O1−γ anode materials are synthesized via a simple ethylene glycol assisted sol-gel method and characterized by X-ray diffraction, Scanning Electron Microscopy, High-resolution/Transmission Electron Microscopy, Energy Dispersive Spectroscopy and Select Area Electron Diffraction. The introduction of potassium element improves the electro-chemical performance of CuO greatly, especially for x = 0.08. After Ag coating, K0.08Cu0.92O1−γ@Ag anode displays superior electro-chemical performance with excellent reversible capacity, cyclic performance and rate capability. It delivers a capacity of 804.3 mA h g−1 even at the 50th cycle. The role played by the K element doping and Ag coating are fully discussed.
Objective The present study examined how sleep duration and sleep quality are associated with cognitive performance in 8-year-old children using standardized neurocognitive tests. Methods Two hundred ninety children aged 7.4–8.8years participated in the study. Sleep duration and quality were measured using actigraphs and the Sleep Disturbance Scale for Parents. Cognitive performance was measured using four subtests of the Wechsler Intelligence Scale for Children III, the Beery Developmental Test of Visual-Motor Integration (VMI), and the Narrative memory subtest of the Developmental Neuropsychological Assessment for Children. Results When adjusting for age, sex, and maternal education, shorter sleep duration, but not sleep quality, was associated with lower visuospatial abilities (p-values ⩽0.043). Sleep duration and quality were not associated with verbal abilities (p-values⩾0.18). With regard to the individual test results, shorter sleep duration was associated with worse performance in Visual-Motor Integration (p =0.028), and when excluding children with high depression scores the same was also true with Block Design (p-values⩽0.047). Moreover, poor sleep efficiency was associated with worse performance in Similarities (p =0.004). Conclusions In a community sample of 8-year-old children, those who slept less or had poorer sleep quality had lower test scores in cognitive tasks, particularly those pertaining to visuospatial performance, although the association was not very strong.