257 research outputs found

    Improved Capacity Retention of SiO2_{2}-Coated LiNi0.6_{0.6}Mn0.2_{0.2}Co0.2_{0.2}O2_{2} Cathode Material for Lithium-Ion Batteries

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    Surface degradation of Ni-enriched layered cathode material Li[Ni0.6Mn0.2Co0.2]O2 (NMC622) is the main reason that leads to large capacity decay during long-term cycling. In the frame of this research, an amorphous SiO2 coating was applied onto the surface of the commercially available NMC622 powder by a wet coating process, through the condensation reaction of tetraethylorthosilicate. The chemical composition of the coating layer was analyzed by inductively-coupled plasma. The morphology was studied by scanning electron microscopy and transmission electron microscopy. Electrochemical properties, including cyclic voltammetry, galvanostatic cycling, and rate capability measurements in a half-cell configuration, were tested to compare the electrochemical behavior of the non-coated and coated NMC622 materials. It is shown that the rate performance of the NMC622 materials is not aected by the coating layer. After 700 cycles in the range of 3.0–4.3 V at 2 C discharge, the cells with SiO2-coated NMC622 materials retained 80% of their initial capacity, which is higher than the uncoated ones (74%). Physicochemical characterizations, e.g., XRD and SEM, were performed post-mortem to reveal the stabilizing mechanism of the SiO2-coated NMC622 electrodes after long-term cycling. Based on these results, this is due to the shielding effect of the coating between the NMC622 particle surface and the liquid electrolyte, along with its scavenging effect on HF. SiO2 coating is therefore a facile surface modification method that results in potentially significant enhancement of the cyclic stability of Ni-rich NMC materials

    Model-Based Design of High Energy All-Solid-State Li Batteries with Hybrid Electrolytes

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    As the aircraft industry becomes more committed to sustainable aviation, hybrid-electric propulsion systems containing batteries with higher gravimetric energy density attract increasing attention to reduce fuel consumption. Future aircrafts could benefit from next-generation chemistries like oxide-based all-solid-state Li-battery (ASSB) technologies. However, producing and evaluating a wide range of design parameters for maximising the gravimetric energy density of ASSB experimentally is both time- and resource-intensive. Physics-based modelling promises to identify optimal designs for battery cells with respect to high gravimetric energy density more time and cost-efficient. In this regard, we applied a pseudo-two-dimensional model for the model-based evaluation of Li-ASSB with various hybrid electrolytes containing oxide and polymer electrolytes. This way we elucidate which electrolyte performs well with present technology and which has the potential to become an attractive alternative in the future. After identifying design variables to improve ASSB with the help of sensitivity analysis, a genetic algorithm is used to predict the optimal design parameters to achieve higher gravimetric energy density. The conducted study reveals that ASSB based on 12.7 vol% of garnet Li6.4_{6.4}La3_{3}Zr1.4_{1.4}Ta0.6_{0.6}O12_{12} (LLZTO) is the best option based on present manufacturing constraints. Hybrid electrolytes based on 10 wt% of Li1.3_{1.3}Al0.3_{0.3}Ti1.7_{1.7}(PO4_{4}) 3_{3}3 (LATP) could be promising for future aircrafts with further improvements in ASSB manufacturing process

    The Effects of Emotional Transmission on Mainstream Social Media A Case Study of Guangming Dailys Account on Douyin

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    Studies on the use of emotional factors by mainstream media mostly start from the perspectives of narrative and content, while few studies focus on the influence of emotional communication. Based on the existing literature on the mainstream media's emotionalized narrative in short videos, this research investigates the influence of this narrative in the process of communication, with a specific focus on the official account of Guangming Daily on Douyin. It combines questionnaires and in-depth interviews. Collected data are analyzed through the tool, Statistical Package for Social Sciences (SPSS) to uncover the effect of emotional content transmission. The result shows that the short videos released by Guangming Daily are characterized by a folk narrative that aims to stimulate emotional resonance. They are of educational significance, providing positive guidance and arousing patriotic feelings

    Impact of Genetic Background on Allele Selection in a Highly Mutable Candida albicans Gene, PNG2

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    In many microbes rapid mutation of highly mutable contingency genes continually replenishes a pool of variant alleles from which the most suitable are selected, assisting in rapid adaptation and evasion of the immune response. In some contingency genes mutability is achieved through DNA repeats within the coding region. The fungal human pathogen Candida albicans has 2600 repeat-containing ORFs. For those investigated (ALS genes, HYR1, HYR2, CEK1, RLM1) many protein variants with differing amino acid repeat regions exist, as expected for contingency genes. However, specific alleles dominate in different clades, which is unexpected if allele variation is used for short-term adaptation. Generation of new alleles of repeat-containing C. albicans ORFs has never been observed directly. Here we present evidence for restrictions on the emergence of new alleles in a highly mutable C. albicans repeat-containing ORF, PNG2, encoding a putative secreted or cell surface glycoamidase. In laboratory cultures new PNG2 alleles arose at a rate of 2.8×10−5 (confidence interval 3.3×10−6−9. 9×10−5) per cell per division, comparable to rates measured for contingency genes. Among 80 clinical isolates 17 alleles of different length and 23 allele combinations were distinguishable; sequence differences between repeat regions of identical size suggest the existence of 36 protein variants. Specific allele combinations predominated in different genetic backgrounds, as defined by DNA fingerprinting and multilocus sequence typing. Given the PNG2 mutation rate, this is unexpected, unless in different genetic backgrounds selection favors different alleles. Specific alleles or allele combinations were not preferentially associated with C. albicans isolates from particular body sites or geographical regions. Our results suggest that the mutability of PNG2 is not used for short-term adaptation or evasion of the immune system. Nevertheless the large number of alleles observed indicates that mutability of PNG2 may assist C. albicans strains from different genetic backgrounds optimize their interaction with the host in the long term

    At-rest lateral earth pressure coefficient under narrow backfill widths: A numerical investigation

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    The lateral earth pressure at rest is typically considered in situations where lateral wall movements are negligible. Determining the coefficient of lateral earth pressure at rest (referred to as K0) often relies on established classical equations. However, these equations often overlook the influence of the width of the backfill soil on lateral earth pressure. While this omission is generally acceptable when the backfill soil is wide enough, there are instances where a retaining wall supports backfill soils of limited width, such as basement walls between adjacent buildings. Yet, there is limited research addressing the impact of narrow backfill in such scenarios. We aimed to address this gap by investigating variations in K0 values under different conditions, including backfill width and soil properties. Using ABAQUS for numerical simulations, we refined and validated our model using relevant laboratory experimental data. Subsequently, the validated model was applied to various simulation scenarios. For narrow backfill widths (ranging from 0.1 to 0.7 times the retaining wall height), our findings indicated a general decrease in K0 values with decreasing backfill widths, often smaller than those estimated using classical equations. Additionally, along the depth of the wall, K0 values tended to decrease with increasing depth for narrow backfill widths. These findings contribute to our understanding of the impact of narrow backfill on K0

    PIT: Optimization of Dynamic Sparse Deep Learning Models via Permutation Invariant Transformation

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    Dynamic sparsity, where the sparsity patterns are unknown until runtime, poses a significant challenge to deep learning. The state-of-the-art sparsity-aware deep learning solutions are restricted to pre-defined, static sparsity patterns due to significant overheads associated with preprocessing. Efficient execution of dynamic sparse computation often faces the misalignment between the GPU-friendly tile configuration for efficient execution and the sparsity-aware tile shape that minimizes coverage wastes (non-zero values in tensor). In this paper, we propose PIT, a deep-learning compiler for dynamic sparsity. PIT proposes a novel tiling mechanism that leverages Permutation Invariant Transformation (PIT), a mathematically proven property, to transform multiple sparsely located micro-tiles into a GPU-efficient dense tile without changing the computation results, thus achieving both high GPU utilization and low coverage waste. Given a model, PIT first finds feasible PIT rules for all its operators and generates efficient GPU kernels accordingly. At runtime, with the novel SRead and SWrite primitives, PIT rules can be executed extremely fast to support dynamic sparsity in an online manner. Extensive evaluation on diverse models shows that PIT can accelerate dynamic sparsity computation by up to 5.9x (average 2.43x) over state-of-the-art compilers

    Towards Achieving Human Parity on End-to-end Simultaneous Speech Translation via LLM Agent

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    In this paper, we present Cross Language Agent -- Simultaneous Interpretation, CLASI, a high-quality and human-like Simultaneous Speech Translation (SiST) System. Inspired by professional human interpreters, we utilize a novel data-driven read-write strategy to balance the translation quality and latency. To address the challenge of translating in-domain terminologies, CLASI employs a multi-modal retrieving module to obtain relevant information to augment the translation. Supported by LLMs, our approach can generate error-tolerated translation by considering the input audio, historical context, and retrieved information. Experimental results show that our system outperforms other systems by significant margins. Aligned with professional human interpreters, we evaluate CLASI with a better human evaluation metric, valid information proportion (VIP), which measures the amount of information that can be successfully conveyed to the listeners. In the real-world scenarios, where the speeches are often disfluent, informal, and unclear, CLASI achieves VIP of 81.3% and 78.0% for Chinese-to-English and English-to-Chinese translation directions, respectively. In contrast, state-of-the-art commercial or open-source systems only achieve 35.4% and 41.6%. On the extremely hard dataset, where other systems achieve under 13% VIP, CLASI can still achieve 70% VIP.Authors are listed in alphabetical order by last name. Demonstrations and human-annotated test sets are available at https://byteresearchcla.github.io/clas

    Efficacy of indigo naturalis nanofibrous patches in the treatment of chronic plaque psoriasis: a 4-week prospective, randomized, semi-compartmental paired, positive drug-controlled trial

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    BackgroundIndigo Naturalis (IN) has been traditionally used for psoriasis treatment. We developed an IN-poly (ε -caprolactone, PCL)/poly (ethylene oxide, PEO) nanofibrous patch using electrospinning technology. Preliminary studies demonstrated its potential to reduces keratinocyte proliferation, inflammation, and neovascularization, addressing limitations of conventional IN formulations such as poor absorption and skin staining.AimsTo evaluate the safety and efficacy of the IN-PCL/PEO patch for chronic plaque psoriasis.MethodsThe clinical trial included 36 patients diagnosed with chronic plaque psoriasis. Two symmetrical psoriatic lesions from each eligible patient were selected by dermatologists and randomly assigned to receive either calcipotriol ointment (control group) or IN-PCL/PEO nanofibrous patch (test group) for 4 weeks. Primary outcomes included Psoriasis Area and Severity Index (PASI), while secondary outcomes assessed Patient Global Assessment (PGA), skin irritation, and patient satisfaction. Safety was monitored via blood, urine, and liver/kidney function tests.Results30 subjects completed the treatment trial with both IN and CA. In the test group (n = 30), PASI scores decreased from 6.30 ± 2.23 to 2.13 ± 1.57 (p < 0.001). Within this group, 90.0% (27/30) achieved PASI 50% and 43.3% (13/30) achieved PASI 75. No skin irritation cases were reported (0.0%). While PASI scores decreased from 6.23 ± 2.27 to 2.23 ± 1.50 (p < 0.001) in the control group, 86.7% (26/30) achieved PASI 50% and 33.3% (10/30) achieved PASI 75, with 6.7% (2/30) experiencing irritation. All safety parameters remained within standard reference ranges.ConclusionThe IN-PCL/PEO patch demonstrated efficacy comparable to calcipotriol ointment, with improved safety and tolerability, suggesting its potential as an alternative psoriasis treatment
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