batterydata/paper-abstracts huggingface dataset:
The design of heterostructured pseudo-capacitive materials plays a key role in fabricating asymmetric supercapacitors (ASCs) with high energy density and electrochemical cycle life for the evolution of next-generation energy storage devices. Use of ZnCo2O4 nanoflakes covered with MnO2 nanosheets led to a synergistic effect that produced a larger electroactive surface area for charge storage than that provided by bare ZnCo2O4 nanoflakes or MnO2 nanosheets. The ZnCo2O4 nanoflakes served as the backbone for the growth of the MnO2 nanosheets. The ZnCo2O4-MnO2 heterostructure was synthesized on Ni foam using a combined binder-free electrodeposition and hydrothermal method. The electrode formed using this unique method showed a maximum specific capacitance of 2057 F g−1 at a current density of 1 A g−1 with a rate capability of 65% even after a 15-fold increase in current density. Moreover, the electrode showed a cycling stability of 96.5% after 5000 successive cycles at a current density of 15 A g−1. An ASC formed using ZnCo2O4-MnO2 as the positive electrode and activated carbon as the negative electrode delivered a maximum energy density of 69 W h kg-1 with 93.5% capacity retention after 5000 cycles. Further, an experiment to investigate the commercial application of ASCs was conducted.
is Head of Product Line Underbody Systems and is Responsible for the Development of New Vehicle Floor Systems at Röchling Automotive SE & Co. KG in Worms (Germany).
The use of industrial by-products such as fly ash and slag have become very prevalent in soil stabilization owing to its suitable physical and mechanical properties, and economical advantages. However, fly ash and slag have been identified as the potential source of toxic substances, and may pose environmental risk by leaching heavy and trace metals into soil, surface and groundwater. Toxicity characteristic leaching procedure (TCLP) tests were conducted to investigate the environmental hazards associated with the leaching of aluminum (Al), copper (Cu), iron (Fe) and zinc (Zn) from fly ashes, slag, type I/II cement and cement activated fly ash and slag stabilized soils. Sulfate (SO4), dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) concentrations were also quantified to evaluate their influence on metal leaching. To understand the effect of pH on the leaching behavior, pH-dependent leach tests were conducted at the pH ranges of 2–14. Results indicated that an increase in fly ash or slag content may not necessarily increase the effluent metal concentrations. Al, Cu, Zn and DOC followed an amphoteric leaching pattern where concentrations increased in both acidic and basic conditions. In contrast, maximum DIC concentrations occurred at neutral or near neutral pH values. Fe and SO4 showed cationic leaching behavior where concentrations decreased with an increase in effluent pH. Additionally, the leaching controlling mechanisms of the metals were identified by implementing geochemical modeling program Visual MINTEQ. The geochemical analyses indicated that the solubility of Al3+ and Fe3+ were controlled by precipitation/dissolution reactions of oxide/hydroxide minerals at all pH values. Leaching of Cu2+ was only solubility controlled at pH higher than 7, whereas Zn2+ leaching was solubility controlled in the pH range of 8–12.
The reduction of transport-generated CO2 emissions is currently a problem of global interest. Hybrid electric vehicles (HEVs) are considered as one promising technological solution for limiting transport-generated greenhouse gas emissions. Currently, the number of HEVs in the market remains limited, but this picture will change in the years to come as HEVs are expected to pave the way for cleaner technologies in transport. In this paper, results are presented regarding fuel economy and pollutant emissions measurements of two hybrid electric production vehicles. The measurements were conducted on a Prius II and a Honda Civic IMA using both the European legislated driving cycle (New European Driving Cycle, NEDC) and real-world simulation driving cycles (Artemis). In addition to the emissions measurements, other vehicle-operating parameters were studied in an effort to better quantify the maximum CO2 reduction potential. Data from real-world operation of a Prius II vehicle were also used in the evaluation. Results indicate that in most cases both vehicles present improved energy efficiency and pollutant emissions compared to conventional cars. The fuel economy benefit of the two HEVs peaked under urban driving conditions where reductions of 60% and 40% were observed, respectively. Over higher speeds the difference in fuel economy was lower, reaching that of conventional diesel at 95kmh−1. The effect of ambient temperature on fuel consumption was also quantified. It is concluded that urban operation benefits the most of hybrid technology, leading to important fuel savings and urban air quality improvement.
NiS2/graphene composite is synthesized by a facile hydrothermal reaction between NiCl2 and l-cysteine in the presence of graphene oxide sheets. l-Cysteine serves as both the sulfur source for NiS2 and reductant for reduction of graphene oxide sheets. The reduced graphene oxides can be used as a platform for growth of NiS2 particles and restrain NiS2 from agglomerating during hydrothermal process. The results of characterizations show that the sphere-like NiS2 particles exhibit smaller sizes and are well dispersed on the surface of reduced graphene sheets. The electrochemical measurements demonstrate that the NiS2/graphene composite delivers a reversible capacity as high as 1200 mAh g−1 at a current density of 100 mA g−1 and enhanced high-rate capability of 740 mAh g−1 at a high current density of 1000 mA g−1. After 1000 cycles, the NiS2/graphene still preserves the reversible capacity about 810 mAh g−1 at a current density of 500 mA g−1, indicating its excellent cyclic stability.
Recently, videoconferencing is becoming more and more pervasive as a consequence of new concerns about privacy and security. The media should be encrypted through the utilization of actual encryption algorithms and group key agreement schemes. In this study, a new key agreement scheme based on Java smart cards is proposed and applied on Web-based real-time communication (WebRTC)-based videoconferencing. In WebRTC, symmetric keys are generated using pseudorandom number generators and shared by two standard protocols, namely, Source Description RTCP Packet (SDES) and Datagram Transport Layer Security (DTLS), through a signaling server. In both methods, the key exchange is open to cryptanalytic attacks, and the administrator of the signaling server can compromise media. This qualitative study aims to investigate privacy during WebRTC-based videoconferencing with respect to symmetric encryption algorithm, randomness of the encryption key, overall security strength, key agreement scheme, and time required to start a conversation. Herein, a new key agreement scheme based on Java smart cards is proposed. The scheme utilizes AES-256 algorithm in GCM mode for media encryption. By means of this approach, the set-up time of a conference is reduced to 562 ms (compared to 1754 ms for the RSA-based approach) for 367 users, and the security strength is increased to 256-bit (as against 112-bit for RSA 2048-bit). A secure random key generator for smart cards is utilized for a key generation instead of pseudorandom number generators. The proposed approach also includes a safety mechanism for smart card failures. We utilize the AVISPA (The Automated Validation of Internet Security Protocols and Applications) tool to test the safety of the proposed scheme.
LiNi0.8Co0.15Al0.05O2 cathode material for lithium-ion batteries is synthesized by sintering the precursor Ni0.8Co0.15Al0.05OOH, which is prepared from the corresponding metal sulphates solution by a co-oxidation-controlled crystallization method. The effects of calcination temperature and time on the electrochemical performance of the material are investigated on the basis of TG-DSC analysis. XRD analyses show that the powders obtained by calcination at 700°C for 6h have the best-ordered hexagonal layer structure. SEM images show that these powders are spherical particles with diameter in the 5–12μm range. The XPS measurement and the chemical titration display that Ni ions of these powders are in the form of Ni3+. The charge–discharge tests demonstrate that these powders have the best electrochemical properties, with an initial discharge capacity of 196.8mAhg−1 and capacity retention of 96.1% after 50 cycles when cycled at a current density of 0.2C between 2.8 and 4.3V. Besides, these powders have also exhibited excellent rate capability and high-temperature performance.
Li x TiP4 ternary phases (x=7 and 9) show very close electrochemical behaviors versus lithium compared to the previously reported Li9VAs4 and Li7VP4. Up to seven lithium ions reversibly react with Li9TiP4, leading to specific and volumetric capacities of 970mAh/g and 1650mAh/cm3, respectively, at average potentials close to 1V. Galvanostatic and potentiodynamic experiments reveal that lithium extraction/insertion follow different mechanisms: a two-phase process is evidenced on charge whereas a more complex process is achieved on discharge. Besides, in situ X-ray diffraction (XRD) patterns show that both Li9TiP4 and Li9VAs4 undergo a reversible crystalline to amorphous structural phase transition upon cycling.
In this study, we modified an attractive water-dispersed poly(acrylonitrile–butylacrylate) binder used for lithium-ion batteries by the addition of highly acidic acrylic acid (AA). The synthesized poly(acrylicacid–acrylonitrile–butylacrylate)–polystyrene polymer showed an improved performance as a binder with smaller particle size, stiffer polymer matrix, higher adhesion strength, and lower contact angle characteristics. Consequently, the modified water-dispersed binder by the addition of AA increased the cyclic capacity and retention of physically mixed silicon/graphite anodes, when compared to the unmodified poly(acrylonitrile–butylacrylate) binder.
Carbon-coated sulfur cathodes were prepared by sputtering method and electrochemical properties of lithium/sulfur cells were investigated. As a result of charge/discharge test, sulfur cathode having carbon layer of 180Å showed the highest capacity of 1178mAhg−1 at first discharge. Moreover, discharge capacity showed about 500mAhg−1 until 50th cycle, which is two times larger than that of no-coated sulfur cathode. This capacity increase could be considered due to the decrease of polysulfides dissolution and the enhancement of electrical contact by surface carbon layer. The changes of sulfur cathode during discharge process were investigated by SEM observation, XRD and DSC measurements. From these results, a discharge reaction mechanism of lithium/carbon-coated sulfur cell was suggested.
Background Sleep deprivation from extended duty hours is a common complaint for many occupations. Caffeine is one of the most common countermeasures used to combat fatigue. However, the benefits of caffeine decline over time and with chronic use. Objective Our objective was to evaluate the efficacy of anodal transcranial direct current stimulation (tDCS) applied to the pre-frontal cortex at 2 mA for 30 min to remediate the effects of sleep deprivation and to compare the behavioral effects of tDCS with those of caffeine. Methods Three groups of 10 participants each received either active tDCS with placebo gum, caffeine gum with sham tDCS, or sham tDCS with placebo gum during 30 h of extended wakefulness. Results Our results show that tDCS prevented a decrement in vigilance and led to better subjective ratings for fatigue, drowsiness, energy, and composite mood compared to caffeine and control in sleep-deprived individuals. Both the tDCS and caffeine produced similar improvements in latencies on a short-term memory task and faster reaction times in a psychomotor task when compared to the placebo group. Interestingly, changes in accuracy for the tDCS group were not correlated to changes in mood; whereas, there was a relationship for the caffeine and sham groups. Conclusion Our data suggest that tDCS could be a useful fatigue countermeasure and may be more beneficial than caffeine since boosts in performance and mood last several hours.
LiNi0.8Co0.2O2 cathode material showed a performance loss after storage in air. The surface species on the material formed during the exposure to air were identified through TG, SEM, TPD-MS, XRD and XPS. Two thin layers were found on the surface. The first layer in contact with the bulk material contains NiO-like species, and the top layer consists of adsorbed hydroxyl, bicarbonate, carbonate, and crystalline Li2CO3. These two layers are both electrochemically inactive and poor conductors for Li+ ions, which are believed to be responsible for the storage loss. A chemical reaction mechanism, involving atmospheric H2O and CO2, and the particle surface of LiNi0.8Co0.2O2 material, was proposed to explain the formation process of those surface species. For storage loss prevention, a doping approach to reduce nickel content and a storage approach to isolate the material from H2O and CO2 were found to be effective to improve the storage property of LiNiO2-based materials. For storage loss recovery, a heat-treatment process at 725°C was demonstrated to be a feasible approach for full recovery of the performance.
In this paper, a 3D (three-dimensional) layer structure of a pouch-type cell is modeled to understand the distribution of temperature and current density across the pouch type Lithium-Ion Battery (LIB). The electrochemical-thermal characteristics are studied, using 1D (one-dimensional) multiphysics model, and simulation results are validated with experimental results. Three-dimensional (3D) modeling of the battery gives the most efficient estimation of energy density, temperature response, overall heat generation and distribution inside the battery. One such 3D electro-thermal model was developed in this work, and the results obtained by the 3D model were validated by using experimental results obtained from LIBs. Temperature profiles of LIB obtained from 3D modeling indicated that the most heat is accumulated around the positive tab of the battery due to non-uniform current distribution and local internal resistance. The presented model can be used as a fast, yet accurate tool, to optimize the cell design for a particular application and for developing battery thermal management systems.
With the potential development of new disease-modifying Alzheimer’s disease (AD) therapies, simple, widely available screening tests are needed to identify which individuals, who are experiencing symptoms of cognitive or behavioral decline, should be further evaluated for initiation of treatment. A blood-based test for AD would be a less invasive and less expensive screening tool than the currently approved cerebrospinal fluid or amyloid β positron emission tomography (PET) diagnostic tests. We examined whether plasma tau phosphorylated at residue 181 (pTau181) could differentiate between clinically diagnosed or autopsy-confirmed AD and frontotemporal lobar degeneration. Plasma pTau181 concentrations were increased by 3.5-fold in AD compared to controls and differentiated AD from both clinically diagnosed (receiver operating characteristic area under the curve of 0.894) and autopsy-confirmed frontotemporal lobar degeneration (area under the curve of 0.878). Plasma pTau181 identified individuals who were amyloid β-PET-positive regardless of clinical diagnosis and correlated with cortical tau protein deposition measured by 18F-flortaucipir PET. Plasma pTau181 may be useful to screen for tau pathology associated with AD.
High-energy density Zinc-air batteries are currently of interest since they could play a key role in emerging large-scale energy storage applications. However, achieving good rechargeability of such metal-air batteries requires significant further research and development effort. Room Temperature Ionic liquids (RTILs) offer a number of ideal thermal and physical properties as potential electrolytes for large-scale energy storage applications and thus, can help increase the practicality of such electrochemical devices. This paper reports the synthesis and application of three novel quaternary alkoxy ammonium bis(trifluoromethylsulfonyl)amide based RTILs, with two or more ether functional groups designed to interact and solubilize zinc ions, in order to aid in the electrochemical reversibility of the metal. The anion is successfully reduced from, and re-oxidized into, the three alkoxy ammonium RTILs suggesting that they are potential candidates as electrolytes for use in zinc-air batteries. Cyclic voltammetry reveals that the presence of water reduces the activation barrier required to deposit zinc and assists stable charge/discharge cycling in an electrolyte consisting of 0.1M Zn(NTf2)2 in the tri-alkoxy ammonium chain RTIL, [N2(20201)(20201)(20201)] [NTf2], with 2.5wt.% H2O. Further experiments demonstrate that with such electrolyte a Zn electrode can complete at least 750 cycles at a current density of 0.1mA/cm2 at room temperature.
Since the ICPD in 1994, the Government of Indonesia has struggled with the challenge of providing sexual and reproductive health education to adolescents. Following an attempt at a family-centred approach, a pilot project was carried out in Central and East Java to train peer educators, coordinated by the National Family Planning Coordinating Board (BKKBN). A total of 80 peer educators (male/female teams) carried out small-group information sessions in ten different districts. Over 1,300 adolescents attended in all. Forty peer counsellors in 20 teams then carried out five outreach sessions each in their communities, attended by nearly 4,000 adults and adolescents. Educators chosen were older in age, knowledge level, authority and communication skills than adolescents, but were well accepted as mentors. Adolescents wanted to know how to deal with sexual relationships and feelings, unwanted pregnancy and STDs. With 42 million Indonesian adolescents needing information, the government cannot produce enough manuals to satisfy demand. New strategies are required to put information in the public domain, e.g. via the media. The approach described in this paper would probably be beyond the staffing and resource capacity of most districts in Indonesia. Nonetheless, it shows that there was great enthusiasm across a variety of communities for efforts to educate young people on protecting their reproductive health.
Solar cell performance parameters (open circuit voltage, short circuit current, fill factor and efficiency) are derived for different solar cell types for the irradiance range 0.1–1000W/m2. Also it is demonstrated how spectral mismatch factors for indoor lighting conditions are calculated. The presented methods and particular results may aid product designers in selecting appropriate solar cells for Product Integrated PV (PIPV) operated indoors and allow for more certainty in energy balance estimations of PIPV design concepts.
The development of low-cost electrode with high capacity and long cycle-life is an essential issue for energy storage devices. Herein a unique nanostructured tetragonal LiMn2O4 (TLMO) electrode exhibiting mixed pseudocapacitor and battery behaviors in Li ion-containing aqueous electrolytes is derived via a novel in-situ low-temperature ion-exchange method from nanocrystalline ZnMn2O4. The complementary actions between the pseudocapacitance and battery properties enable TLMO to substantially outperform, in terms of the combination of high capacity, long cycle stability and suppressed self-discharge, its counterparts having only either one of the electrochemical behaviors, along with many other notable pseudocapacitive materials. The phase transformation mechanism during the ion-exchange process and charge-storage mechanisms are revealed using operando/in situ synchrotron X-ray analyses. This study may open up a new design concept in charge-storage electrode materials.
Although psychiatric symptom severity and impairment are overlapping but nevertheless distinct illness parameters, little research has examined whether variables found to be associated with the severity are also correlated with symptom-induced impairment. Parents and teachers completed ratings of symptom-induced impairment for DSM-IV-referenced syndromes, and parents completed a background questionnaire for a consecutively referred sample of primarily male (81 %) 6-to-12 year olds with autism spectrum disorder (ASD) (N = 221). Some clinical correlates (e.g., IQ < 70, maternal level of education, pregnancy complications, current use of psychotropic medication, season of birth) were associated with impairment for several disorders, whereas others were correlated with only a few syndromes (e.g., gender, co-morbid medical conditions) or were not related to impairment in any disorder (e.g., family psychopathology). There was little convergence in findings for parents’ versus teachers’ ratings. Some clinical correlates (e.g., season of birth, current psychotropic medication, maternal education) were unique predictors of three or more disorders. Pregnancy complications were uniquely associated with social anxiety and schizoid personality symptom-induced impairment. IQ was a unique predictor of schizophrenia, ASD, oppositional defiant disorder symptom-induced impairment. Children whose mothers had relatively fewer years of education had greater odds for symptom-induced impairment in social anxiety, depression, aggression, and mania and greater number of impairing conditions. Season of birth was the most robust correlate of symptom-induced impairment as rated by teachers but not by parents. Children born in fall evidenced higher rates of co-occurring psychiatric and ASD symptom-induced impairment and total number of impairing conditions. Many variables previously linked with symptom severity are also correlated with impairment.
The objective of the study was to determine the prevalence and associated factors for temporomandibular disorders (TMD) in a university sample of Campeche, Mexico. A cross-sectional study was carried out in 506 subjects aged 14–25 years. The subjects were requested to answer questionnaires concerning sociodemographic variables, history of stress, lifestyle, and anxiety. The Research Diagnostic Criteria for TMD (RDC/TMD) was used as TMD diagnostic system by four examiners capacitated and standardized. Data were analyzed using binary logistic regression in STATA. The results showed that 46.1% of the subjects exhibited some grade of TMD. Logistic regression analysis with TMD as the dependent variable identified sex (women odds ratio [OR]=1.7), bruxism (OR=1.5), anxiety (OR=1.6), unilateral chewing (OR=1.5), and an interaction between number of tooth loss and stress as the most significant associated variables, thus (1) the effect of having high levels of stress in the group of subjects without tooth loss (OR=1.2; 95% confidence interval [CI]=0.7–1.8) and (2) the effect of having high levels of stress in the group of subjects with at least one tooth lost (OR=2.4; 95% CI=1.01–5.9). The variables associated with diagnosis of pain were principally psychosocial (stress and anxiety), whereas for the non-pain diagnosis group, the variables were clinical, such as bruxism, chewing site preference, and restorations in mouth. We found associations among variables that were similar to findings in other studies, such as bruxism, tooth loss, stress, and anxiety. The final model explains that the effect of stress on TMD depends of the tooth loss, controlling for sex, bruxism, unilateral chewing, and anxiety. Finally, it can be concluded that the variables associated with pain and non-pain diagnosis were of distinct nature.