batterydata/paper-abstracts huggingface dataset:
Co(OH)2 nanosheets, which obtained from Polyvinyl Pyrrolidone (PVP) improved solution-phase synthesis, can be transformed to porous Co3O4 nanoplates by solid-state crystal reconstruction during heat treatment in air. Transmission electron microscopy (TEM) indicates that the transformation process and final crystal structure are strongly dependent on the temperature of heat treatment. When the temperature is increased to 500 °C, the mesoporous and single-crystal Co3O4 nanoplates with an average size of around 1 μm can be obtained by solid-state diffusion, coalescence and following orientational alignment. Electrochemical tests show that the lithium storage performance of porous Co3O4 nanoplates is associated more closely with its structural aspects than its morphology and size factors. The obtained plate-like Co3O4 mesocrystals exhibit low initial irreversible capacity and superior cycling performance due to its micrometer size, porous and robust single-crystal structure. Considering the improved electrochemical performance, simple and large scale synthesis, the obtained 2D Co3O4 mesocrystals should be suitable as anode materials for high performance lithium-ion batteries.
Electrodes in high-energy all-solid-state lithium batteries are typically composites, consisting of mixtures of a Li storage material and a solid electrolyte. Ion transport in such composite electrodes plays an important role for battery performance. A key parameter characterizing effectiveness of ion transport is the tortuosity. While the tortuosity of separators and porous electrodes used in liquid-electrolyte batteries has been already investigated, there is a lack of data for electrodes of all-solid-state batteries. In this work, we present results for the tortuosity of a typical composite cathode, consisting of LiCoO2 active material particles and a sulfide-based solid electrolyte. To get values for tortuosity, two different approaches were followed. The first one is based on impedance spectroscopic measurements of the stationary Li+ current across the composite. The second approach combines three-dimensional reconstruction of the electrode structure based on focused ion-beam scanning electron microscopy with numerical simulations of ion transport in the reconstructed electrode. The presented results demonstrate a significant effect of residual voids in the composite electrode on the ion transport tortuosity. Careful attention should therefore be paid to the actual amount of void space formed during the preparation of composite electrodes as key component of all-solid-state batteries.
This paper summarizes battery thermal modeling capabilities for: (1) an advanced vehicle simulator (ADVISOR); and (2) battery module and pack thermal design. The National Renewable Energy Laboratory’s (NREL’s) ADVISOR is developed in the Matlab/Simulink environment. There are several battery models in ADVISOR for various chemistry types. Each one of these models requires a thermal model to predict the temperature change that could affect battery performance parameters, such as resistance, capacity and state of charges. A lumped capacitance battery thermal model in the Matlab/Simulink environment was developed that included the ADVISOR battery performance models. For thermal evaluation and design of battery modules and packs, NREL has been using various computer aided engineering tools including commercial finite element analysis software. This paper will discuss the thermal ADVISOR battery model and its results, along with the results of finite element modeling that were presented at the workshop on “Development of Advanced Battery Engineering Models” in August 2001.
Wristbands are increasingly used for assessing personal chemical exposures. Unlike some exposure assessment tools, guidelines for wristbands, such as preparation, applicable chemicals, and transport and storage logistics, are lacking. We tested the wristband’s capacity to capture and retain 148 chemicals including polychlorinated biphenyls (PCBs), pesticides, flame retardants, polycyclic aromatic hydrocarbons (PAHs), and volatile organic chemicals (VOCs). The chemicals span a wide range of physical–chemical properties, with log octanol–air partitioning coefficients from 2.1 to 13.7. All chemicals were quantitatively and precisely recovered from initial exposures, averaging 102% recovery with relative SD ≤21%. In simulated transport conditions at +30 °C, SVOCs were stable up to 1 month (average: 104%) and VOC levels were unchanged (average: 99%) for 7 days. During long-term storage at −20 °C up to 3 (VOCs) or 6 months (SVOCs), all chemical levels were stable from chemical degradation or diffusional losses, averaging 110%. Applying a paired wristband/active sampler study with human participants, the first estimates of wristband–air partitioning coefficients for PAHs are presented to aid in environmental air concentration estimates. Extrapolation of these stability results to other chemicals within the same physical–chemical parameters is expected to yield similar results. As we better define wristband characteristics, wristbands can be better integrated in exposure science and epidemiological studies.
Microbial fuel cells were designed and operated to treat landfill leachate while simultaneously producing electricity. Two designs were tested in batch cycles using landfill leachate as a substrate without inoculation (908 to 3,200 mg/L chemical oxygen demand (COD)): Circle (934 mL) and large-scale microbial fuel cells (MFC) (18.3 L). A total of seven cycles were completed for the Circle MFC and two cycles for the larger-scale MFC. Maximum power densities of 24 to 31 mW/m2 (653 to 824 mW/m3) were achieved using the Circle MFC, and a maximum voltage of 635 mV was produced using the larger-scale MFC. In the Circle MFC, COD, biological oxygen demand (BOD), total organic carbon (TOC), and ammonia were removed at an average of 16%, 62%, 23%, and 20%, respectively. The larger-scale MFC achieved an average of 74% BOD removal, 27% TOC removal, and 25% ammonia reduction while operating over 52 days. Analysis of the microbial characteristics of the leachate indicates that there might be both supportive and inhibiting bacteria in landfill leachate for operation of an MFC. Issues related to scale-up and heterogeneity of a mixed substrate remain.
The operating temperatures of lithium ion battery packs in electrical vehicles and hybrid electrical vehicles need to be maintained in an optimum range for better performance and longer battery life. This paper proposes a new battery pack cooling system that utilizes the low saturation temperature of the fuel in ammonia based future hybrid electric vehicles. In the proposed cooling system, the batteries are partially submerged in to the liquid ammonia, and the liquid ammonia cools the battery by absorbing the heat and evaporating and the ammonia vapor cools the part of the battery not covered by liquid ammonia. The relationships between the performance of the battery cooling system and the maximum temperature (and the temperature distribution) in the battery are investigated for practical applications. The effect of the length of the battery that is submerged in to the liquid ammonia on the thermal performance of battery is studied and evaluated. The present results show that the proposed ammonia based cooling system offers a unique opportunity to maintain the operating temperature of the battery in an optimum range for consecutive charging and discharging phases at a high rate of 7.5C.
A simple and versatile method for preparation of novel manganese 2,5-thiophene dicarboxylate microspheres is developed via a surfactant-assisted solvo-thermal route, which are found to be a new high-energy anode material for lithium-ion batteries. It shows better cycling performance and higher discharge capacity than its counterpart of irregular shapes. A reversible capacity was achieved as high as 645.7mAhg−1 after 250 cycles at a current density of 400mAg−1. Furthermore, the coulombic efficiency can be close to 100% even after 650 charge-discharge cycles at a current density of 500mAg−1.
Although mobile devices have been considerably upgraded to more powerful terminals, yet their lightness feature still impose intrinsic limitations in their computation capability, storage capacity and battery lifetime. With the ability to release and augment the limited resources of mobile devices, mobile cloud computing has drawn significant research attention allowing computations to be offloaded and executed on remote resourceful infrastructure. Nevertheless, circumstances like mobility, latency, applications execution overload and mobile device state; any can affect the offloading decision, which might dictate local execution for some tasks and remote execution for others. We present in this article a novel system model for computations offloading which goes beyond existing works with smart centralized, selective, and optimized approach. The proposition consists of (1)hotspots selection mechanism to minimize the overhead of the offloading evaluation process yet without jeopardizing the discovery of the optimal processing environment of tasks, (2)a multi-objective optimization model that considers adaptable metrics crucial for minimizing device resource usage and augmenting its performance, and (3)a tailored centralized decision maker that uses genetics to intelligently find the optimal distribution of tasks. The scalability, overhead and performance of the proposed hotspots selection mechanism and hence its effect on the decision maker and tasks dissemination are evaluated. The results show its ability to notably reduce the evaluation cost while the decision maker was able in turn to maintain optimal dissemination of tasks. The model is also evaluated and the experiments prove its competency over existing models with execution speedup and significant reduction in the CPU usage, memory consumption and energy loss.
A counter flow membraneless microfluidic fuel cell is presented, where a non-reacting electrolyte separates the reacting streams. In this fuel cell design, vanadium reactants flow through porous carbon electrocatalysts. A sulfuric acid stream is introduced in the gap between the electrodes and diverts the reactants to opposite and independent outlets. This fuel cell differs from other membraneless designs in its ability to maintain a constant separation between the reactants without diffusive mixing.
This exploratory study targets married, heterosexual couples living in Sarasota County, Florida and uses a dyadic interview approach to understand how the interactions of married couples, or intra-household dynamics, could affect household hurricane preparedness. Interview results reveal that couples consider household hurricane preparedness to be a joint process between husband and wife, but in many cases, partners do not have the same opinions about these preparations. This study also shows the relations between household hurricane preparedness and household division of labor, and how the tendency of wives to prioritize relational preparedness activities could be an answer to understanding why some quantitative studies show that females have lower preparedness levels than males. Other potential problems with this previous research, including the selection of survey participants and the measurement of household hurricane preparedness, are likewise discussed.
Introduction: Systemic juvenile arthritis - a rare chronic disease. Register - it's an important tool to monitor the effectiveness and safety of GIBP.
Two kinds of functionalized graphene sheets were produced by thermal exfoliation of graphite oxide. The first kind of functionalized graphene sheets was obtained by thermal exfoliation of graphite oxide at low temperature in air. The second kind was prepared by carbonization of the first kind of functionalized graphene sheets at higher temperature in N2. Scanning electron microscopy images show that both two kinds of samples possess nanoporous structures. The results of N2 adsorption–desorption analysis indicate that both of two kinds of samples have high BET surface areas. Moreover, the second kind of functionalized graphene sheets has a relatively higher BET surface area. The results of electrochemical tests is as follows: the specific capacitance values of the first kind of functionalized graphene sheets in aqueous KOH electrolyte are about 230Fg−1; the specific capacitance values of the second kind of functionalized graphene sheets with higher BET surface areas are only about 100Fg−1; however, compared with the first kind of functionalized graphene sheets, the second kind has a higher capacitance retention at large current density because of its good conductive behaviors; furthermore, in non-aqueous EC/DEC electrolyte, the specific capacitance values of the first kind sample and the second kind sample are about 73Fg−1 and 36Fg−1, respectively.
Electric vehicles can become integral parts of a smart grid, since they are capable of providing valuable services to power systems other than just consuming power. On the transmission system level, electric vehicles are regarded as an important means of balancing the intermittent renewable energy resources such as wind power. This is because electric vehicles can be used to absorb the energy during the period of high electricity penetration and feed the electricity back into the grid when the demand is high or in situations of insufficient electricity generation. However, on the distribution system level, the extra loads created by the increasing number of electric vehicles may have adverse impacts on grid. These factors bring new challenges to the power system operators. To coordinate the interests and solve the conflicts, electric vehicle fleet operators are proposed both by academics and industries. This paper presents a review and classification of methods for smart charging (including power to vehicle and vehicle-to-grid) of electric vehicles for fleet operators. The study firstly presents service relationships between fleet operators and other four actors in smart grids; then, modeling of battery dynamics and driving patterns of electric vehicles, charging and communications standards are introduced; after that, three control strategies and their commonly used algorithms are described; finally, conclusion and recommendations are made.
As part of multidisciplinary surveys of three Behavioural Phenotype Conditions (BPCs); Möbius sequence (Möbius), CHARGE syndrome (CHARGE) and oculo-auriculo-vertebral spectrum (OAV), autism spectrum conditions (ASCs) was diagnosed in 45%, 68% and 42% of the individuals, respectively. Diagnostic difficulties due to additional dysfunctions such as mental retardation (MR), impaired vision, reduced hearing and cranial nerve dysfunction, were experienced in all three BPC groups. The applicability of current autism diagnostic instruments, such as the Autism Diagnostic Interview-Revised (ADI-R), the Childhood Autism Rating Scale (CARS) and the Autistic Behaviour Checklist (ABC), in individuals with ASCs and Möbius/CHARGE/OAV was analysed. Use of an extensive battery of diagnostic instruments, including both observational schedules and parent interviews, and, if possible, independent judgements from two clinicians, is essential in the diagnostics of ASCs in these individuals. Further, in individuals who are deaf and blind the applicability of current autism diagnostic instruments is highly questionable.
The study examines the effectiveness of a career intervention in middle schools. The intervention was organized in eight 45-minute-long group sessions. A quasi-experimental pre- and post-test design was applied, with 120 students in the experimental group and 156 in the control group. Small- to medium-size effects were found in terms of reduction of lack of career information and an increase in independence in career decision-making. The observed effects were stable across gender and for high and low school achievers.
Since July 2002, tertiary treated wastewater has been artificially recharged through two infiltration ponds in the dunes of the Belgian western coastal plain. This has formed a lens of artificially recharged water in the dunes’ fresh water lens. Recharged water is recovered by extraction wells located around the ponds. Hydraulic aspects of the artificial recharge and extraction are described using field observations such as geophysical borehole loggings and a tracer test. Borehole logs indicate recharged water up to 20 m below surface, whereas the tracer test gives field data about the residence times of the recharged water. Furthermore, a detailed solute transport model was made of the area surrounding the ponds. Groundwater flow, capture zone, residence times and volume of recharged water in the aquifer are calculated. This shows that the residence time varies between 30 days and 5 years due to the complex flow pattern. The extracted water is a mix of waters with different residence times and natural groundwater, assuring a relatively stable water quality of the extracted water.
The distributed generation (DG) of combined heat and power (CHP) for commercial buildings is gaining increased interest, yet real-world installations remain limited. This lack of implementation is due, in part, to the challenging economics associated with volatile utility pricing and potentially high system capital costs. Energy technology application analyses are also faced with insufficient knowledge regarding how to appropriately design (i.e., configure and size) and dispatch (i.e., operate) an integrated CHP system. Existing research efforts to determine a minimum-cost-system design and dispatch do not consider many dynamic performance characteristics of generation and storage technologies. Consequently, we present a mixed-integer nonlinear programming (MINLP) model that prescribes a globally minimum cost system design and dispatch, and that includes off-design hardware performance characteristics for CHP and energy storage that are simplified or not considered in other models. Specifically, we model the maximum turn-down, start up, ramping, and part-load efficiency of power generation technologies, and the time-varying temperature of thermal storage technologies. The consideration of these characteristics can be important in applications for which system capacity, building demand, and/or utility guidelines dictate that the dispatch schedule of the devices varies over time. We demonstrate the impact of neglecting system dynamics by comparing the solution prescribed by a simpler, linear model with that of our MINLP for a case study consisting of a large hotel, located in southern Wisconsin, retrofitted with solid-oxide fuel cells (SOFCs) and a hot water storage tank. The simpler model overestimates the SOFC operational costs and, consequently, underestimates the optimal SOFC capacity by 15%.
The multi-walled carbon nanotube (CNT)-embedded activated carbon nanofibers (ACNF/CNT) and activated carbon nanofibers (ACNF) were prepared by stabilizing and activating the non-woven web of polyacrilonitrile (PAN) or PAN/CNT prepared by electrospinning. Both ACNF and ACNF/CNT were partially aligned along the winding direction of the drum winder. The average diameter of ACNF was 330nm, while that of ACNF/CNT was lowered to 230nm with rough surface. This was attributed to the CNT-added polymer solution in the electrospinning process providing finer fibers by increasing the electrical conductivity compared with the CNT-free one. The specific surface area and electrical conductivity of ACNF were 984m2/g and 0.42S/cm, respectively, while those of ACNF/CNT were 1170m2/g and 0.98S/cm, respectively. PPy was coated on the electrospun ACNF/CNT (PPy/ACNF/CNT) by in situ chemical polymerization in order to improve the electrochemical performance. The capacitances of the ACNF and PPy/ACNF electrodes were 141 and 261F/g at 1mA/cm2, respectively, whereas that of PPy/ACNF/CNT was 333F/g. This improvement in capacitance was attributed to the following: (i) the preparation of aligned nano-sized ACNF/CNT by electrospinning and the addition of CNT and (ii) the formation of a good charge-transfer complex by the PPy coating on the surface of the aligned nano-sized ACNF/CNT. The former leads to a good morphology and superior properties, such as a higher surface area, the formation of mesopores and an increase in electrical conductivity. The latter offers a refined three-dimensional network due to the highly porous structure between ACNF/CNT and PPy.
This paper adopts the concept of `environmental imaginaries' to explore the influence of environmental discourses upon supporters of Australian environmental movements. Rather than investigate knowledge, values, attitudes or behaviour, as is often the focus of research into public environmentalism, this study analyses the presence, absence, influence and interactions of different environmental discourses at the interpersonal scale. The relative acceptability and familiarity of different environmental philosophies, with their radically different approaches to nature, has important impacts upon the political strategies, actions and directions adopted by environmental movements. Through conducting a series of ongoing discussion groups with self-identifying `environmentalists' it is found that nature is constructed predominantly through the language and concepts of sustainable development, although this discourse coexists with a number of concurrent and oppositional viewpoints. The power of sustainable development is self-sustained through the normalisation of particular languages and modes of expression. Alternative ideas and discourses are inhibited by a lack of language and familiarity and consequently disempowered and relegated to subordinate positions within discussions. The paper concludes by arguing that the lack of acceptance of alternative ecocentric ideas within the environmental community risks de-radicalising the movement and limits the diversity of political strategies and options that it could potentially adopt.
Carbon-encapsulated LiMn2O4 (LMO@C) spheres were prepared using polymer microgel reactor, in which Mn2+ ions are hydrolyzed in situ to form Mn(OH)2, and followed by annealing at a high temperature. The LMO@C spheres are constructed with the spinel LiMn2O4 nanospheres that embedded in a porous carbon matrix uniformly. Owing to possessing three-dimensional (3D) electron-conductive and 3D ion-conductive networks, the LMO@C spheres exhibit high rate capability. They can deliver the specific capacities of 142, 137, 126, 107, and 91 mAh g−1 at the rates of 0.1C, 1C, 5C, 10C, and 20C (1C = 148 mA g−1), respectively. Owing to carbon encapsulation, the LMO@C spheres can retain 80% of the initial capacity at 1C rate after 1000 cycles at 25 °C, displaying stable cycling performance. The results suggest that the LMO@C spheres are promising cathode materials for high-power lithium-ion batteries.
In this paper, Artificial Neural Network (ANN) power management for a reverse osmosis desalination unit fed by hybrid renewable energy sources solar PV and wind turbine associated to battery bank as storage element is studied. The ANN power management system has as main objective to ensure the smooth transfer of the generated power by these sources under the variability and intermittency of the wind speed and the irradiation during 24 h of operation considering the limitation constraints of the RO unit and the need water profile. The design, the modeling and the control strategies of all the components are made in this study using Matlab/Simulink. The results show the ability of the ANN power manager to define the operating modes based on the proposed flow chart.