batterydata/paper-abstracts huggingface dataset:
Ag@LiFePO4 cathode materials have been prepared successfully by performing solid-state reactions between AgNO3 and the ascorbic acid in the presence of LiFePO4 powders at ambient temperature. Metallic Ag nanoparticles of ca. 10 nm in diameter can be produced with the environmental benign approach and efficiently attached onto the surfaces of commercial LiFePO4 cathode materials. The as-prepared composites show highly enhanced electrochemical performances in storing Li with ca. 22% increase in their discharge specific capacity from 128 to 156 mAhg−1 at C/10 rate, after loading Ag additive of 2 wt%. The coulombic efficiency of the composites can retain 97%, after cycling for 80 times. They can also remain up to 94 mAhg−1 of their discharge specific capacity at high rate of 5 C, which is almost twice higher than that of LiFePO4 cathode materials.
The strontium doped Mn-based perovskites have been proposed as one of the best oxygen reduction reaction catalysts (ORRCs) to substitute the noble metal. However, few studies have investigated the catalytic activities of LSM with the A-site deficiencies. Here, the (La1-xSrx)0.98MnO3 (LSM) perovskites with A-site deficiencies are prepared by a modified solid-liquid method. The structure, morphology, valence state and oxygen adsorption behaviors of these LSM samples are characterized, and their catalytic activities toward ORR are studied by the rotating ring-disk electrode (RRDE) and aluminum-air battery technologies. The results show that the appropriate doping with Sr and introducing A-site stoichiometry can effectively tailor the Mn valence and increase the oxygen adsorption capacity of LSM. Among all the LSM samples in this work, the (La0.7Sr0.3)0.98MnO3 perovskite composited with 50% carbon (50%LSM30) exhibits the best ORR catalytic activity due to the excellent oxygen adsorption capacity. Also, this catalyst has much higher durability than that of commercial 20%Pt/C. Moreover, the maximum power density of the aluminum-air battery using 50%LSM30 as the ORRC can reach 191.3 mW cm−2. Our work indicates that the LSM/C composite catalysts with A-site deficiencies can be used as a promising ORRC in the metal-air batteries.
Juvenile dermatomyositis (JDM) is a rare, often chronic, systemic autoimmune disease of childhood, characterized by inflammation of the microvasculature of the skeletal muscle and skin. Prominent clinical features include significant exercise intolerance, muscle weakness, and fatigue. Despite pharmacological improvements, these clinical features continue to affect patients with JDM, even when the disease is in remission. Exercise training is increasingly utilized as a non-pharmacological intervention in the clinical management of (adult) patients with chronic inflammatory conditions; however no randomized controlled trials (RCT) have been performed in JDM. In the current study, the efficacy and feasibility of an exercise training program in patients with JDM will be examined.
We prepared mono/bi-layer iron phosphate two-dimensional (2D) materials with 0.74nm/1.52nm thickness by means of a simple chemically induced precipitation method and post-processing. The mechanism of growth of the atomically thin 2D-sheet crystals was investigated by experimental measurements and theoretical calculations. The crystalline 2D sheets were easily oxidized to the amorphous phase in air, and LiFePO4 nano-crystals self-nucleated from amorphous 2D sheets in the charge/discharge process. The 2D sheets show excellent performance properties as cathode materials: high initial discharge capacity of 185mAhg−1 at 0.1C, stable cycling (98% capacity retention over 400 cycles), and high rate capability (107mAhg−1 at 20C) for Li-ion storage. A model for self-nucleation of the LiFePO4 nano-crystals involving double-center diffusion is discussed.
The purpose of the present study was to investigate the role of phonological encoding in the silent speech of persons who stutter (PWS) and persons who do not stutter (PNS). Participants were 10 PWS (M =30.4 years, S.D.=7.8), matched in age, gender, and handedness with 11 PNS (M =30.1 years, S.D.=7.8). Each participant performed five tasks: a familiarization task, an overt picture naming task, a task of self-monitoring target phonemes during concurrent silent picture naming, a task of monitoring target pure tones in aurally presented tonal sequences, and a simple motor task requiring finger button clicks in response to an auditory tone. Results indicated that PWS were significantly slower in phoneme monitoring compared to PNS. No significant between-group differences were present for response speed during the auditory monitoring, picture naming or simple motor tasks, nor did the two groups differ for percent errors in any of the experimental tasks. The findings were interpreted to suggest a specific deficiency at the level of phonological monitoring, rather than a general monitoring, reaction time or auditory monitoring deficit in PWS. Educational objectives: As a result of this activity, the participant should: (1) identify and assess the literature on phonological encoding skills in PWS, (2) enumerate and evaluate some major psycholinguistic theories of stuttering, and (3) describe the mechanism by which defective phonological encoding can disrupt fluent speech production.
Mechanical reperfusion with primary percutaneous coronary intervention in acute ST-segment-elevation myocardial infarction is superior to fibrinolysis in terms of short-term and long-term outcome, provided that it can be delivered on time and by an experienced team. Balloon angioplasty and stent implantation of an occluded epicardial vessel during ST-segment-elevation myocardial infarction can cause disruption of the frail thrombus containing lesions associated with suboptimal myocardial reperfusion and microcirculatory obstruction. Distal embolization of atherothrombotic material can be prevented by thrombus aspiration during primary angioplasty. Mechanical aspiration via end-hole large-lumen thrombectomy catheters has been shown to improve Thrombolysis in Myocardial Infarction (TIMI) flow and result in a more consistent early resolution of ST-segment elevation in multiple registries. More recently, a more sophisticated quantification of the myocardial damage has been applied using myocardial scintigraphy and magnetic resonance, with no difference between patients treated with thrombectomy and patients treated with conventional therapy. The expectations in terms of lasting mortality benefit raised by the first Dutch single-center randomized trial of thrombectomy versus predilation with plain old balloon angioplasty (Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction, TAPAS) were not confirmed by a much larger Swedish trial (Thrombus Aspiration ST-Segment Elevation Myocardial Infarction, TASTE) showing no outcome changes. Although we are waiting for new trials to clarify these controversial results, thrombectomy is still used in selected patients with high thrombus load or with persistent occlusion of the infarct-related artery after wire passage. Here we review the various systems available and discuss their relative merits and the reported results.
The peroxisome proliferator-activated receptor-α (PPARα) regulates lipid homeostasis, particularly in the liver. This study was aimed at elucidating the relationship between hepatosteatosis and oxidative stress during fasting. Fasted Ppara-null mice exhibited marked hepatosteatosis, which was associated with elevated levels of lipid peroxidation, nitric oxide synthase activity, and hydrogen peroxide accumulation. Total glutathione (GSH), mitochondrial GSH, and the activities of major antioxidant enzymes were also lower in the fasted Ppara-null mice. Consequently, the number and extent of nitrated proteins were markedly increased in the fasted Ppara-null mice, although high levels of protein nitration were still detected in the fed Ppara-null mice while many oxidatively modified proteins were only found in the fasted Ppara-null mice. However, the role of inflammation in increased oxidative stress in the fasted Ppara-null mice was minimal based on the similar levels of tumor necrosis factor-α change in all groups. These results with increased oxidative stress observed in the fasted Ppara-null mice compared with other groups demonstrate a role for PPARα in fasting-mediated oxidative stress and that inhibition of PPARα functions may increase the susceptibility to oxidative damage in the presence of another toxic agent.
To examine the evidence of the feasibility, acceptability, and potential efficacy of online supportive care interventions for people living with and beyond lung cancer (LWBLC).
Lithium-ion batteries are used for energy storage in a wide array of applications, and do not always undergo full charge and discharge cycling. This study quantifies the effect of partial charge-discharge cycling on Li-ion battery capacity loss by means of cycling tests conducted on graphite/LiCoO2 pouch cells under different state of charge (SOC) ranges and discharge currents. The results are used to develop a model of capacity fade for batteries under full or partial cycling conditions. This study demonstrates that all of the variables studied including mean SOC, change in SOC (ΔSOC) and discharge rate have a significant impact on capacity loss rate during the cycling operation. This study is useful in identifying the SOC ranges with slow degradation rates.
Redox mediators facilitate the oxidation of the highly insulating discharge product in metal–oxygen batteries during recharge and offer opportunities to achieve high reversible capacities. Now a design principle for selecting redox mediators that can recharge the batteries more efficiently is suggested.
Electrolyte additives are known to improve the performance of lithium-ion cells. In this work we examine the performance of Li1.03Ni0.5Mn0.3Co0.3O2-graphite (NMC532/Gr) cells containing combinations of lithium bis(oxalate)borate (LiBOB), vinylene carbonate (VC), trivinylcyclotriboroxane (tVCBO), prop-1-ene-1,3-sultone (PES), phenyl boronic acid ethylene glycol ester (PBE), tris(trimethylsilyl) phosphite (TMSPi), triethyl phosphite (TEPi), and lithium difluoro(oxalate)borate (LiDFOB) added to our baseline (1.2 M LiPF6 in EC:EMC, 3:7 w/w) electrolyte. In order to rank performance of the various electrolytes, we developed two separate figures of merit (FOM), which are based on the energy retention and power retention of the cells. Using these two metrics in conjunction, we show that only one of the fifteen electrolyte formulations tested significantly outperforms the baseline electrolyte: this electrolyte contains the 0.25 wt% tVCBO + 1 wt% TMSPi additive mix. Little correlation was observed between the FOMs for energy retention and power retention, which indicates that the mechanisms that govern these performance parameters are likely independent of each other. Our FOM approach has general applicability and can be used to develop electrolyte and electrode formulations that prolong the life of lithium-ion batteries.
Advances in high throughput and high content (HT/HC) methods such as those used in the fields of toxicogenomics, bioinformatics, and computational toxicology have the potential to improve both the efficiency and effectiveness of toxicity evaluations and risk assessments. However, prior to use, scientific confidence in these methods should be formally established. Traditional validation approaches that define relevance, reliability, sensitivity and specificity may not be readily applicable. HT/HC methods are not exact replacements for in vivo testing, and although run individually, these assays are likely to be used as a group or battery for decision making and use robotics, which may be unique in each laboratory setting. Building on the frameworks developed in the 2010 Institute of Medicine Report on Biomarkers and the OECD 2007 Report on (Q)SAR Validation, we present constructs that can be adapted to address the validation challenges of HT/HC methods. These are flexible, transparent, and require explicit specification of context and purpose of use such that scientific confidence (validation) can be defined to meet different regulatory applications. Using these constructs, we discuss how anchoring the assays and their prediction models to Adverse Outcome Pathways (AOPs) could facilitate the interpretation of results and support scientifically defensible fit-for-purpose applications.
With the increasing energy demands for electronic devices and electrical vehicles, anode materials for lithium ion batteries (LIBs) with high specific capacity, good cyclic and rate performances become one of the focal areas of research. Among the various anode materials, SnO2/graphene nanocomposites have drawn extensive attentions due to their high theoretical specific capacities, low charge potential vs. Li/Li+ and environmental benignity. In this review, the advances, including the synthetic methods and structural optimizations, of the SnO2/graphene nanocomposites as anode materials for LIBs have been reviewed in detail. By providing an in-depth discussion of SnO2/graphene nanocomposites, we aim to demonstrate that the electrochemical performances of SnO2/graphene nanocomposites could be significantly enhanced by rational modifications of morphology and crystal structures, chemical compositions and surface features. Though only focusing on SnO2/graphene-based composites, the concepts and strategies should be referential to other metal oxide/graphene composites.
LiFePO4 electrode material with large specific surface area and porous structure can achieve high energy and power capabilities, but current synthesis method is relatively complicated. Here, we report a facile synthesis of porous–LiFePO4/C (porous–LFP/C) nanocomposites, which require no templates or surfactants. The synthesized porous–LFP/C material possesses outstanding morphology with nano-sized, spherical particles, a desirable core–shell structure with uniform carbon film on the surface of LiFePO4 and with a specific surface area of 29.9 m2 g−1. The as-obtained porous–LFP/C nanocomposites show excellent rate capability and cycling stability. It delivers a discharge capacity of 143 and 126 mAh g−1 at 5C and 10C rates, respectively, and exhibits desirable capacity retention after 500 cycles. Remarkably, it performed well even at 30C (83 mAh g−1) with the 91% of initial capacity after 1000 cycles.
The lower extremities are important to performing physical activities of daily life. This study investigated lower extremity tissue composition, i.e. muscle and fat volumes, in young and older adults and the relative importance of individual tissue compartments to the physical function of older adults. A total of 43 older (age 78.3±5.6years) and 20 younger (age 23.8±3.9years) healthy men and women participated in the study. Older participants were further classified as either high- (HF) or low-functioning (LF) according to the Short Physical Performance Battery (SPPB). Magnetic resonance images were used to determine the volumes of skeletal muscle, subcutaneous fat (SAT), and intermuscular fat (IMAT) in the thigh (femoral) and calf (tibiofibular) regions. After adjusting for the sex of participants, younger participants had more femoral muscle mass than older adults (p<0.001 for between group differences) as well as less femoral IMAT (p=0.008) and tibiofibular IMAT (p<0.001). Femoral muscle was the only tissue compartment demonstrating a significant difference between the two older groups, with HF participants having 31% more femoral muscle mass than LF participants (mean difference=103.0±34.0cm3; p=0.011). In subsequent multiple regression models including tissue compartments and demographic confounders, femoral muscle was the primary compartment associated with both SPPB score (r2 =0.264, p=0.001) and 4-meter gait speed (r2 =0.187, p=0.007). These data suggest that aging affects all lower extremity compartments, but femoral muscle mass is the major compartment associated with physical function in older adults.
The pH sensitivity of electrically conducting polyaniline (PANI) and its derivatives poly(o-methylaniline) (PoMeANI), poly(o-ethylaniline) (PoEtANI), poly(o-propylaniline) (PoPrANI) and poly(N-methylaniline) (PNMeANI) have been studied with potentiometry and UV–vis spectroscopy. The electropolymerisation of PANI was carried out either in hydrochloric acid (HCl), methanesulphonic acid (MSA), benzenesulphonic acid (BSA) or dodecylbenzenesulphonic acid (DBSA). It is shown that the pH sensitivity of PANI and its derivatives depend on the substituent and the size of the acid anion that is used in the electropolymerisation. PANI membranes prepared in HCl show a selective and slightly super-Nernstian potentiometric pH response (62.4±0.9 mV per pH; pH 2–9), while PNMeANI, PoPrANI and PANI prepared with DBSA have a strongly suppressed pH response. The hysteresis effect observed in the UV–vis measurements for all membrane types studied restrict the use of PANI-based optical pH sensors to the pH range of only 5–8.
Although its formative years began in the 1940s, a critical mass of therapeutic medical technologies has emerged over the past 25 years, and they set the foundation for a significant new industry. The impact of these technologies has been greatest in orthopedics, cardiovascular disease, and neurological disorders. During this same period, imaging technologies have transformed diagnostics. Engineering education has also evolved dramatically, from the application of classical engineering disciplines to solve medical problems to a revolutionary biology-based engineering perspective that is emerging today. This expanding portfolio of engineering capabilities predicts an exciting possibilities for patients suffering from serious diseases as innovative new medical technologies are developed to moderate symptoms, restore function and, on the horizon, replace failing organs with living engineered ones.
An optimized combination of reduction by methane and sulfuric acid digestion was developed to improve the electrochemical activity of manganese dioxide at a battery set. Chemical manganese dioxide, CMD, and electrolytic manganese dioxide, EMD, which have been destroyed after discharge cycling process in potential window of 900–1650mV versus Hg/HgO, were reduced in a furnace with a flow of methane at 300 and 250°C correspondingly. Thereafter, the reduced samples, CMDr and EMDr, were digested in a solution of sulfuric acid with optimized concentration and temperature. It was found that digested samples, CMDro and EMDro, typically show more stability in cycling, higher capacity and more reversible redox reaction. Alternatively, we reported about the effect of digestion temperature on electrochemical and structural properties of the samples. Digestion at temperatures 60 and 98°C in 1.5M sulfuric acid as superior concentration was preferred after comparative experiments in the range 40–98°C. The samples which were digested in 60°C (CMDro1 and EMDro1) showed superior electrochemical activity at the early stages of discharge cycling. By contrast, the samples which were obtained at 98°C (CMDro2 and EMDro2) showed more stability and were superior to the former samples in final stages of discharge cycling process. Afterward, the electrochemical behavior of the pretreated samples was investigated by means of cyclic voltammetry technique and discharge cumulative capacity profiles. Also X-ray diffraction was employed to verify the responses of voltammetric methods. In XRD patterns, peak at 2θ =28.6° which is due to β-MnO2 type was the strongest signal as temperature 98°C was selected for digestion. After digestion at 60°C, the characteristic peaks at 2θ =38° and 42° were amplified which are attributed to formation of γ-MnO2. Interestingly enough, the results according to the XRD patterns were in good agreement with the electrochemical approaches.
The effect of rapid thermal annealing (RTA) on the surface of a LiNi1−x Co x O2 cathode film is examined by means of scanning electron microscopy (SEM), atomic force microscopy (AFM) and auger electron spectroscopy (AES). It is found that the as-deposited LiNi1−x Co x O2 film undergoes a surface reaction with oxygen in the air, due to the high activity of lithium in the film. AES spectra indicate that the surface layer consists of lithium and oxygen atoms. The RTA process at 500°C eliminates the surface layer to some extent. An increase in annealing temperature to 700°C results in complete elimination of the surface layer. The surface evolution of the LiNi1−x Co x O2 film with increasing annealing time at 700°C is examined by means of AFM examination. It is found that the surface layer, which is initially present in the form of an amorphous like-film, becomes agglomerated and then vaporizes after 5min of annealing. A thin-film microbattery (TFB), fabricated by using the LiNi1−x Co x O2 film without a surface layer, exhibits more stable cycliability and a higher specific discharge capacity of 60.2μAhcm−2 μm than a TFB with an unannealed LiNi1−x Co x O2 film. Therefore, it is important to completely eliminate the surface layer in order to achieve high performance from all solid-state thin-film microbatteries.
Lithium intercalation into graphite electrodes is widely studied, but few direct in situ diagnostic methods exist. Such diagnostic methods are desired to probe the influence of factors such as charge rate, electrode structure and solid electrolyte interphase layer transport resistance as they relate to lithium-ion battery performance and durability. In this work, we present a continuous measurement of through-plane lithium distributions in a composite graphite/lithium metal electrochemical cell. Capacity change in a thick graphite electrode was measured during several charge/discharge cycles with high resolution (14μm) neutron imaging. A custom test fixture and a method for quantifying lithium are described. The measured lithium distribution within the graphite electrode is given as a function of state of charge. Bulk transport resistance is considered by comparing intercalation rates through the thickness of the electrode near the separator and current collector. The residual lithium content associated with irreversible capacity loss that results from cycling is also measured.
In this work, C-graphene composed of core graphene and carbon shells was prepared to obtain a new type of carbon electrode materials. Carbon shells containing nitrogen groups were prepared by coating polyaniline (PANI) onto graphene by in situ polymerization and subsequent carbonization at 850°C. After carbonization, the C-graphene contained 6.5% nitrogen and showed a 2D plate structure and crystallinity like that of pristine graphene. In addition, the C-graphene exhibited electrochemical performance superior to that of pristine graphene, and the highest specific capacitance (170F/g) of the C-graphene was obtained at a scan rate of 0.1A/g, as compared to 138F/g for pristine graphene. This superior performance was attributed to the synergistic effect of porous carbon layer and the graphene and the pseudocapacitive effect by the nitrogen groups formed on the carbon electrode after carbonization.
Li1+x V3O8 is a very promising cathode material for lithium secondary batteries. A novel technique has been developed to prepare Li1+x V3O8. The V2O5 sol is prepared via a “quencher” method by NH4VO3 as the raw material. Then it is mixed with LiOH solution. The spherical precursor is obtained by a spray drying method. Spherical Li1+x V3O8 powders are synthesized by sintering the spherical precursor. DTA/TGA is employed to analyze the precursor. The influences of the preparing conditions including initial ratio of Li/V, sintering time and temperature on crystal structure and electrochemical performance have been investigated. As a result, the Li1+x V3O8 particles obtained by sintering at 350°C for 24h are fine, spherical, narrowly distributed, well crystallized and having excellent electrochemical properties.