16 research outputs found

    Performance evaluation of a scaled-up membraneless organic-based hybrid flow battery

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    This article presents an evaluation of the performance of a membrane-less organic-based flow battery using low-cost active materials, zinc and benzoquinone, which was scaled up to 1600 cm2, resulting in one of the largest of its type reported in the literature. The charge–discharge cycling of the battery was compared at different sizes and current densities, and its performance was evaluated under various mass transport and operating conditions. The results showed that the round-trip coulombic and voltage efficiencies were over 90% and 85%, respectively, for the laboratory-scale (1 cm2 electrode) cell, but these performances tended to deteriorate with the scaled-up (1600 cm2 electrode) cell due to inadequate mass transfer and sediment coverage of quinone, as well as the formation of a passivation film on the zinc anode. Despite this, the scaled-up batteries exhibited high coulombic and voltage efficiencies of up to 99% and 68.5%, respectively, at a current density of 10 mA cm−2. The capital cost of this system is also estimated to be several times lower than those of commercially available all-vanadium flow batteries and zinc bromide flow batteries for demand charge management applications

    A numerical model of a zinc-para-benzoquinone membrane-free organic flow battery

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    Organic flow batteries have received a great deal of interest in the past five years as potential candidates for large-scale energy storage, due to their low costs, abundant active materials and multi-electron transfers. Membrane-less systems are particular attractive given the cost of high-performance membranes such as Nafion©. To overcome known limitations, and to design and optimize new systems, modeling and simulation can play a vital role. In this paper, a two-dimensional transient model of a membrane-less zinc-quinone flow battery incorporating the conservation of mass, charge and momentum in the battery and reservoir is developed and validated. The performance is studied under the influence of different electrolyte flow regimes and variations in key parameters, in order to provide new insights and recommendations for further development of the system, as well as similar systems

    A Stochastic Simulation Model for Monthly River Flow in Dry Season

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    Streamflow simulation gives the major information on water systems to water resources planning and management. The monthly river flows in dry season often exhibit high autocorrelation. The headwater catchment of the Yellow River basin monthly flow series in dry season exhibits this clearly. However, existing models usually fail to capture the high-dimensional, nonlinear dependence. To address this issue, a stochastic model is developed using canonical vine copulas in combination with nonlinear correlation coefficients. Kendall’s tau values of different pairs of river flows are calculated to measure the mutual correlations so as to select correlated streamflows for every month. Canonical vine copula is used to capture the temporal dependence of every month with its correlated streamflows. Finally, monthly river flow by the conditional joint distribution functions conditioned upon the corresponding river flow records was generated. The model was applied to the simulation of monthly river flows in dry season at Tangnaihai station, which controls the streamflow of headwater catchment of Yellow River basin in the north of China. The results of the proposed method possess a smaller mean absolute error (MAE) than the widely-used seasonal autoregressive integrated moving average model. The performance test on seasonal distribution further verifies the great capacity of the stochastic-statistical method

    The role of Traditional Chinese medicine in anti-HBV: background, progress, and challenges

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    Abstract Chronic hepatitis B (CHB) remains a major world's most serious public health issues. Despite the remarkable effect of nucleos(t)ide analogues (NAs) in inhibiting hepatitis B virus (HBV) deoxyribonucleic acid (DNA) as the first-line drug, there are several limitations still, such as poor antigen inhibition, drug resistance, low-level viremia, restricting patients' functional cure. Due to the constraints of NAs, traditional medicines, such as traditional Chinese medicine (TCM), have become more prevalently used and researched in the clinical treatment of CHB as complementary alternative therapies. As a consequence, the review focuses on the background based on HBV’s life cycle as well as the NAs’ limitations, progress based on direct and indirect pathway of targeting HBV of TCM, and challenges of TCM. We found TCMs play an increasingly important role in anti-HBV. In a direct antiviral way, they regulate HBV infection, replication, assembly, and other aspects of the HBV life cycle. As for indirect way, TCMs can exert anti-HBV effects through targeting the host, including immune regulation, apoptosis, autophagy, oxidative stress, etc. Especially, TCMs have the advantages of strong antigenic inhibition compared to NAs. Specifically, we can combine the benefits of TCMs in strong HBV antigen inhibition with the benefits of NAs in targeted antiviral effects, in order to find a suitable combination of "TCM + NAs" to contribute to Chinese knowledge of the realisation of the “global elimination of HBV by 2030” goal of the World Health Organization

    Facile spray-printing of hydrophobic and porous gas diffusion electrodes enabling prolonged electrochemical CO2 reduction to ethylene

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    The twelve-electron carbon dioxide reduction reaction (12e– CO2RR) constitutes a sustainable alternative to steam cracking for the production of ethylene (C2H4), the world’s most coveted organic compound. State-of-the-art gas diffusion electrodes (GDEs), while exhibiting promising faradaic efficiencies for C2H4 electrosynthesis, suffer from poor long-term stability, particularly at elevated applied currents, due to catalyst delamination and flooding of the diffusion layer. Herein, through the development and optimisation of a novel, facile and flexible spray-printing method, hydrophobic porous carbon and copper electrodes with different architectures are obtained readily by using suspensions consisting of two fugitive solvents, which provide larger surface areas for the three-phase boundary and improve the hydrophobicity/flooding tolerance of the electrodes, due to their increased surface roughness and binder (PVDF) content. These structures, with pore sizes as low as 60 ÎŒm, transform the surfaces from incomplete wetting to highly hydrophobic, and can be employed as gas-diffusion, microporous or supportive layers, in addition to acting as a supporting substrate for the copper-based catalyst. These layers are spray-printed in a stacked assembly upon polymer film and carbon paper substrates, and ultimately result in an extended duration of enhanced C2H4 production at applied currents of up to 200 mA cm-2 via multiple configurations. Through layer-by-layer spray-printing with a hydrophobic microporous layer and porous catalyst support, this inventive approach can efficiently control the hydrophobicity of the GDE, and extends the cathode operation time by a factor of 6, with a maximum faradaic efficiency of 52% attained, and an average of > 30% maintained over 12 h of continuous electrolysis, demonstrating the versatility of this technique for engineering highly durable GDEs for selective CO2 reduction toward multi-carbon (C2+) commodities, energy storage devices and other electrochemical applications

    iTRAQ-Based Membrane Proteomics Reveals Plasma Membrane Proteins Change During HepaRG Cell Differentiation

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    HepaRG cell, a stabilized bipotent liver progenitor cell line, exhibits hepatocyte functions only after differentiation. However, the mechanism of transition from nondifferentiated to differentiated states, accompanied by proliferation migration and differentiation, remains poorly understood, particularly those proteins residing in the plasma membrane. In this study, the membrane protein expression change of HepaRG cell during differentiation were systematically analyzed using an iTRAQ labeled quantitative membrane proteomics approach. A total of 70 membrane proteins were identified to be differentially expressed among 849 quantified membrane proteins. Function and disease clustering analysis proved that 11 of these proteins are involved in proliferation, migration, and differentiation. Two key factors (MMP-14 and OCLN) were validated by qRT-PCR and Western blot. Blockade of MMP-14 further demonstrated its important function during tumor cell migration. The data sets have been uploaded to ProteomeXchange with the identifier PXD004752

    Combined GWAS and eQTL analysis uncovers a genetic regulatory network orchestrating the initiation of secondary cell wall development in cotton

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    The cotton fiber serves as a valuable experimental system to study cell wall synthesis in plants, but our understanding of the genetic regulation of this process during fiber development remains limited. We performed a genome‐wide association study (GWAS) and identified 28 genetic loci associated with fiber quality in allotetraploid cotton. To investigate the regulatory roles of these loci, we sequenced fiber transcriptomes of 251 cotton accessions and identified 15,330 expression quantitative trait loci (eQTL). Analysis of local eQTL and GWAS data prioritized 13 likely causal genes for differential fiber quality in a transcriptome‐wide association study (TWAS). Characterization of distal eQTL revealed unequal genetic regulation patterns between two subgenomes, highlighted by an eQTL hotspot (Hot216) that establishes a genome‐wide genetic network regulating the expression of 962 genes. The primary regulatory role of Hot216, and specifically the gene encoding a KIP‐related protein, was found to be the transcriptional regulation of genes responsible for cell wall synthesis, which contributes to fiber length by modulating the developmental transition from rapid cell elongation to secondary cell wall synthesis. This study uncovers the genetic regulation of fiber‐cell development and reveals the molecular basis of the temporal modulation of secondary cell wall synthesis during plant cell elongation

    Polymorphisms of the FAS and FASL genes and risk of breast cancer

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    FAS and its ligand FASL are crucial in apoptotic cell death. Loss of FAS and gain of aberrant FASL expression are common features of malignant transformation. This study was designed to investigate whether the functional polymorphisms of FAS -1377G/A (rs2234767) and FASL -844T/C (rs763110) affect the risk of developing breast cancer. Genotypes were analyzed by a polymerase chain reaction-restriction fragment length polymorphism assay in 436 breast cancer patients and 496 healthy controls. In this study, as compared to the wild-type homozygote and heterozygote, the distribution of the FAS -1377GG, GA and AA genotypes among breast cancer patients were significantly different from those among healthy controls (P=0.011), with the AA genotype being more prevalent among patients than the controls (P=0.003). Similarly, the frequencies of the FASL -844TT, TC and CC genotypes also significantly differed among breast cancer patients and healthy controls (P<0.001), with the CC genotype being significantly over-represented in breast cancer patients compared with the controls (P<0.001). In the unconditional logistic regression model following adjustment for age, the subjects carrying the FAS -1377AA genotype had a 1.75-fold increased risk [95% confidence interval (CI), 1.13–2.69] for development of breast cancer compared with patients carrying the GG genotype. Similarly, in the recessive model, the FASL -844CC genotype significantly increased the risk of breast cancer with an odds ratio (OR) of 1.92 (95% CI 1.46–2.54) compared with the TT or TT + TC genotypes. Our results suggest that functional polymorphisms in the death pathway genes FAS and FASL significantly contribute to the occurrence of breast cancer
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