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Nickel sulfides with high theoretical capacity are considered as promising anode materials for sodium-ion batteries (SIBs); however, their intrinsic poor electric conductivity, large volume change during charging/discharging, and easy sulfur dissolution result in inferior electrochemical performance for sodium storage. Herein, a hierarchical hollow microsphere is assembled from heterostructured NiS/NiS2 nanoparticles confined by in situ carbon layer (H-NiS/NiS2 @C) via regulating the sulfidation temperature of the precursor Ni-MOFs. The morphology of ultrathin hollow spherical shells and confinement of in situ carbon layer to active materials provide rich channels for ion/electron transfer and alleviate the effects of volume change and agglomeration of the material. Consequently, the as-prepared H-NiS/NiS2 @C exhibit superb electrochemical properties, satisfactory initial specific capacity of 953.0 mA h g-1 at 0.1 A g-1 , excellent rate capability of 509.9 mA h g-1 at 2 A g-1 , and superior longtime cycling life with 433.4 mA h g-1 after 4500 cycles at 10 A g-1 . Density functional theory calculation shows that heterogenous interfaces with electron redistribution lead to charge transfer from NiS to NiS2 , and thus favor interfacial electron transport and reduce ion-diffusion barrier. This work provides an innovative idea for the synthesis of homologous heterostructures for high-efficiency SIB electrode materials.
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Transition-metal selenides have been considered as one of the most promising anode materials for sodium-ion batteries (SIBs) due to their high theoretical capacity and excellent rate performance. However, rapid capacity decay and poor cycling stability limit their practical application as the anode for SIBs. Carbon coating is one of the most effective ways to solve the above problems, but the thickness and uniformity of the coating layer are difficult to control. Herein, we successfully synthesize metal-organic framework (MOF)-derived porous N-doped carbon nanocubes homogeneously filled with ZnSe and Co0.85Se and interconnected by reduced graphene oxide (ZCS@NC@rGO). ZCS@NC@rGO with more active sites and the synergistic effect of the ZnSe and Co0.85Se heterojunction can enhance the sodium storage performance. The porous carbon nanocubes effectively prevent the agglomeration of active particles, and the rGO acting as a carbon network can significantly buffer the inevitable volume changes. At the same time, carbon nanocubes and the rGO are interconnecting to form a conductive network to accelerate electron transfer. Based on the aforementioned advantages, the ZCS@NC@rGO electrode shows an excellent sodium storage performance. Our investigation opens up a new horizon for the rational design of transition-metal selenide anodes for SIBs with a unique structure.
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Electrochemical reduction is an eco-friendly alternative for energy-saving artificial N2 fixation. The development of this process requires efficient N2 reduction reaction (NRR) electrocatalysts to overcome the challenge with N2 activation. We show that a Cr2O3 nanoparticle-reduced graphene oxide hybrid (Cr2O3-rGO) is as an outstanding catalyst for electrochemical N2-to-NH3 conversion under ambient conditions. In 0.1 M HCl, Cr2O3-rGO achieves a high NH3 yield of 33.3 µg h-1 mg-1cat. at -0.7 V vs RHE and a high Faradaic efficiency of 7.33% at -0.6 V vs RHE, with excellent selectivity for NH3 synthesis and stability. Density functional theory calculations were executed to gain further insight into the mechanisms.
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It is highly attractive to construct natural enzyme-free nanoarray architecture as a 3D catalyst for hydrogen peroxide detection due to its great specific surface area and easy accessibility to target molecules. In this communication, we demonstrate that nickel borate nanoarray supported on carbon cloth (Ni-Bi/CC) behaves as an efficient catalyst electrode for H2 O2 electro-reduction in neutral media. As a non-enzymatic electrochemical H2 O2 sensor, such Ni-Bi/CC shows superior sensing performances with a fast response time (less than 3â s), a low detection limit (0.85â nm, S/N=3), and a high sensitivity (18320â µA mm cm-2 ). Importantly, it also demonstrates favourable reproducibility and long-term stability.
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Environmentally friendly electrochemical hydrogen production needs the development of earth-abundant catalyst materials for the hydrogen evolution reaction with high activity and durability at neutral pH. In this work, the self-templating construction of a hollow amorphous CoMoS4 nanotube array on carbon cloth (CoMoS4 NTA/CC) is reported, using hydrothermal treatment of a Co(OH)F nanowire array on CC in (NH4 )2 MoS4 solution. When used as a 3D electrode for hydrogen evolution electrocatalysis, the resulting CoMoS4 NTA/CC demonstrates superior catalytic activity and strong long-term electrochemical durability in 1.0â M phosphate buffer solution (pH=7). It shows small onset overpotential of 21â mV and requires low overpotentials of 104 and 179â mV to drive geometrical current densities of 10 and 50â mA cm-2 , respectively. Density functional theory calculations suggest that CoMoS4 has a more favorable hydrogen adsorption free energy than Co(OH)F.
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Searching for a simple and fast strategy to effectively enhance the oxygen evolution reaction (OER) performance of non-noble-metal electrocatalysts in alkaline media remains a significant challenge. Herein, the OER activity of NiFe-LDH nanoarray on carbon cloth (NiFe-LDH/CC) in alkaline media is shown to be greatly boosted by an amorphous NiFe-Borate (NiFe-Bi ) layer formation on NiFe-layered double hydroxide (NiFe-LDH) surface. Such a NiFe-LDH@NiFe-Bi /CC catalyst electrode only needs an overpotential of 294â mV to drive 50â mA cm-2 in 1.0 m KOH; 116â mV less than that needed by NiFe-LDH/CC. Notably, this electrode also demonstrates strong long-term electrochemical durability. The superior activity is ascribed to the pre-formed amorphous NiFe-Bi layer effectively promoting active species generation on the NiFe-LDH surface. This work opens up exciting new avenues for developing high-performance water-oxidation catalyst materials for application.
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porcine reproductive and respiratory syndrome (PRRS), caused by porcine reproductive and respiratory syndrome virus (PRRSV) infection, is an important swine infectious disease that causes substantial losses worldwide each year. PRRSV is a positive-sense single-stranded RNA virus that is highly susceptible to mutation and recombination, making vaccine and drug research for the disease extremely difficult. In this study, the binding of PRRSV nsp2 to HSP71 protein was detected by using the IP/MS technique. And the inhibitory effect of HSP71 on nsp2 antagonistic activity was validated by measuring NF-kB luciferase reporter. According to stress from inhibitory effects, the amino acid variation profile of PRRSV nsp2 under HSP71 stress was further analyzed using second-generation sequencing. Surprisingly, the results indicated that HSP71 pressure limits the random mutations of PRRSV nsp2 and maintains the dominant PRRSV strain within the population. Mutant strain showed weaker antagonistic activity and replication capability in cell. These results imply the binding of HSP71 with PRRSV nsp2 may lead to maintain the stability of highly virulent strains of PRRSV.
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Mutação , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Proteínas não Estruturais Virais , Replicação Viral , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Animais , Suínos , Síndrome Respiratória e Reprodutiva Suína/virologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Linhagem Celular , Ligação Proteica , NF-kappa B/metabolismo , NF-kappa B/genéticaRESUMO
Designing an earth-abundant and cost-effective electrocatalyst for oxygen evolution reaction (OER) is the crux to the hydrogen production by water electrolysis on industrial scale. Herein, we developed a trimetallic sulfide hybrid of CoS1.097/Fe1-xS/Ni3S2/NF nanoarrays by the combination of morphology optimization and interface modulation. The unique morphology of ultrathin nanosheets significantly enriches the reaction sites of the catalyst, while the abundant heterogeneous interfaces effectively regulate the local electron structure and thus intrinsically enhances the catalytic activity of the material. As a result, the catalyst delivers the superior OER performance with the ultralow overpotential of 229 mV at the current density of 50 mA cm-2 and Tafel slope of 30.2 mV dec-1. Furthermore, the current density of the material keeps constant for 50 h in 1.0 M KOH. This work proposes a strategy for the synthesis of polymetallic sulfide catalysts with composite structure as an efficient OER catalyst by morphology optimization and interface modulation.
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The Li2S-P2S5 pseudo-binary system has been a valuable source of promising superionic conductors, with α-Li3PS4, ß-Li3PS4, HT-Li7PS6, and Li7P3S11 having excellent room-temperature Li-ion conductivity >0.1 mS/cm. The metastability of these phases at ambient temperature motivates a study to quantify their thermodynamic accessibility. Through calculating the electronic, configurational, and vibrational sources of free energy from first principles, a phase diagram of the crystalline Li2S-P2S5 space is constructed. New ground-state orderings are proposed for α-Li3PS4, HT-Li7PS6, LT-Li7PS6, and Li7P3S11. Well-established phase stability trends from experiments are recovered, such as polymorphic phase transitions in Li7PS6 and Li3PS4, and the instability of Li7P3S11 at high temperature. At ambient temperature, it is predicted that all superionic conductors in this space are indeed metastable but thermodynamically accessible. Vibrational and configurational sources of entropy are shown to be essential toward describing the stability of superionic conductors. New details of the Li sublattices are revealed and are found to be crucial toward accurately predicting configurational entropy. All superionic conductors contain significant configurational entropy, which suggests an inherent correlation between fast Li diffusion and thermodynamic stability arising from the configurational disorder.
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Aqueous rechargeable Zn-ion batteries (ARZIBs) are promising for energy storage. However, the Zn dendrite and corrosive reactions on the surface of Zn anode limit the practical uses of ARZIBs. Herein, we present a valid electrolyte additive of NaI, in which I- can modulate the morphology of Zn crystal growth by adsorbing on specific crystal surfaces (002), and guide Zn deposition by inducing a negative charge on the Zn anode. Simultaneously, it enhances the reduction stability of water molecules by participating in the solvation structure of Zn(H2O)62+ by forming ZnI(H2O)5+. At 10 mA cm-2, the assembled Zn symmetrical batteries can run stably over 1,100 h, and the depth of discharge (DOD) can reach 51.3 %. At 1 A g-1, the VO2||Zn full-cell in 2 M ZnCl2 electrolyte with 0.4 M NaI (2 M ZnCl2-0.4 M NaI) maintains of the capacity retention of 75.7 % over 300 cycles. This work offers an insight into inorganic anions as electrolyte additives for achieving stable zinc anodes of ARZIBs.
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Improving the efficiency of the anodic oxygen evolution reaction (OER) is important to solve the global energy crisis and greenhouse gas emission problems. In this paper, a preparation method for a MIL-53(Fe)@ZIF-67(Co) composite electrode is proposed. The hierarchical structure formed by the combination of MIL-53(Fe) and ZIF-67(Co) provides a rich channel for the transport of electrons and mass in the OER process. XPS analysis and DFT calculations revealed that Fe electrons in MIL-53(Fe) were transferred to Co in ZIF-67(Co) through O, which confirmed the rapid charge transfer effect of this transport channel. The MIL-53(Fe)@ZIF-67(Co) electrode has significant OER performance. When the current density reaches 10 mA cm-2, the overpotential is only 193 mV. This study inaugurates a new way for the rational design of a multiphase interface and the construction of new MOF channel structures.
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Designing and developing earth-abundant electrocatalysts for the oxygen evolution reaction (OER) in alkaline media is a critical element in the societal development of sustainable energy. MIL-53(Fe-Ni)/NF-2200Gs was synthesized under an external magnetic field. Such MIL-53(Fe-Ni)/NF-2200Gs show exceptionally high catalytic activity and require an overpotential of only 174 mV to drive a geometrical catalytic current density of 10 mA cm-2 in 1.0 M KOH, superior to RuO2 and most Fe, Ni-based electrocatalysts. Our work emphasizes the optimization of catalytic activity originating from the improvement of the magnetic properties of the catalyst, which enhances the spin polarization and tailors the d-electron structure of cations, leading to outstanding OER activity. This work would open new opportunities to design and develop transition-metal-based nanometer arrays toward efficient and stable water oxidation in alkaline media for applications.
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Dietary alkaloid nuciferine isolated from the leaves of Nelumbo nucifera can ameliorate dyslipidemia and liver lipid accumulation, but the underlying mechanism remains unclear. Caspase recruitment domain protein family member 6 (CARD6) is suggested to play an important role in metabolic diseases. This study aimed to investigate the role and the upstream regulator of CARD6 in high fructose-induced liver lipid accumulation and whether and how the anti-lipid accumulation effect of nuciferine was related to CARD6. Herein, we found that high fructose decreased CARD6 expression and increased ASK1 and JNK1/2 phosphorylation in rat livers and hepatocytes, which were attenuated by nuciferine. Furthermore, after the transfection with HA-CARD6, CARD6 siRNA and MIB2 siRNA, the data showed that CARD6 overexpression blocked high fructose-induced upregulation of ASK1 and JNK1/2 phosphorylation as well as lipid accumulation in hepatocytes. CARD6 siRNA reversed the amelioration of nuciferine to high fructose-induced upregulation of ASK1 and JNK1/2 phosphorylation in hepatocyte lipid accumulation. Mechanistically, high fructose upregulated MIB2 expression by interacting with CARD6 and promoting K48-linked CARD6 polyubiquitination and degradation in high fructose-stimulated hepatocytes which were explored by immunoblotting, immunofluorescence, and immunoprecipitation. However, MIB2 siRNA reversed high fructose-induced downregulation of CARD6 and lipid accumulation in hepatocytes. Notably, nuciferine reduced MIB2 expression and thus decreased K48-linked CARD6 polyubiquitination and degradation in the amelioration of high fructose-induced lipid accumulation in hepatocytes. These results suggested that nuciferine exhibited a protective effect against high fructose-induced liver lipid accumulation through blocking MIB2-mediated CARD6 polyubiquitination and degradation.
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Fígado Gorduroso , Frutose , Ratos , Animais , Frutose/efeitos adversos , Frutose/metabolismo , Fígado Gorduroso/metabolismo , Fígado/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismoRESUMO
OBJECTIVE: Dim target detection in remote sensing images is a significant and challenging problem. In this work, we seek to explore event-related brain responses of dim target detection tasks and extend the brain-computer interface (BCI) systems to this task for efficiency enhancement. METHODS: We develop a BCI paradigm named Asynchronous Visual Evoked Paradigm (AVEP), in which subjects are required to search the dim targets within satellite images when their scalp electroencephalography (EEG) signals are simultaneously recorded. In the paradigm, stimulus onset time and target onset time are asynchronous because subjects need enough time to confirm whether there are targets of interest in the presented serial images. We further propose a Domain adaptive and Channel-wise attention-based Time-domain Convolutional Neural Network (DC-tCNN) to solve the single-trial EEG classification problem for the AVEP task. In this model, we design a multi-scale CNN module combined with a channel-wise attention module to effectively extract event-related brain responses underlying EEG signals. Meanwhile, domain adaptation is proposed to mitigate cross-subject distribution discrepancy. RESULTS: The results demonstrate the superior performance and better generalizability of this model in classifying the single-trial EEG data of AVEP task in contrast to typical EEG deep learning networks. Visualization analyses of spatiotemporal features also illustrate the effectiveness and interpretability of our proposed paradigm and learning model. CONCLUSION: The proposed paradigm and model can effectively explore ambiguous event-related brain responses on EEG-based dim target detection tasks. SIGNIFICANCE: Our work can provide a valuable reference for BCI-based image detection of dim targets.
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Interfaces Cérebro-Computador , Eletroencefalografia , Algoritmos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Humanos , Redes Neurais de Computação , Couro CabeludoRESUMO
In this work, we report the design and synthesis of non-noble metal-based electrocatalysts for effective overall water splitting in alkaline solutions for the development of hydrogen energy. The electrocatalysts were synthesized by a one-step hydrothermal method similar to microflower structure electrocatalysts. The synergistic effect between the special Echinops sphaerocephalus nanostructure and the nanowire can greatly improve the conductivity of the nanomaterial due to its high activity quality, fast ion transport, and exposure of more active sites, thus resulting in a better catalytic activity and a longer material stability of the electrocatalyst. For MnxCoyO4/Ti in alkaline aqueous solutions, a current density of 10 mA cm-2 is required when the voltage is only 1.60 V. In addition, the hydrogen evolution activity of electrocatalysts is 168 mV at 10 mA cm-2, the Tafel slope is 174 mV dec-1, and the oxygen evolution activity of electrocatalysts is 229 mV at 10 mA cm-2, which showed good long-term stability within 12 h, even better than that of previously reported electrocatalysts.
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Recently, zinc metal has been considered as a promising metal anode for aqueous rechargeable metal ion batteries due to its low electrochemical potential and high theoretical capacity. However, zinc metal suffers from hydrogen evolution reaction (HER) and dendrite growth during plating/stripping. Here, we propose a low-cost, effective and non-toxic electrolyte additive, tetramethylammonium sulfate hydrate (TMA2SO4), as a simple cationic surfactant additive for zinc-ion batteries, to trigger the smooth Zn deposition during charging and discharging process. It is found that TMA2SO4 enable the realization of the deposition of Zn ions along the surface of zinc foil laterally without stacking and thus dendrite growth and side reactions are greatly mitigated by the electrolyte additive of TMA2SO4 even when the amount of the additive is as low as 0.25 mM. As a result, the TMA2SO4 additive induces excellent cycling stability over 1800 h at the current density of 0.5 mA cm-2 with the limited capacity of 0.5 mAh cm-2 for the Zn-Zn symmetrical cell. Moreover, the electrolyte with TMA2SO4 can well match with MnO2 cathode, which achieves the high initial capacity of 181.3 mAh g-1 at 0.2 A g-1 and long-term cycling stability with the capacity retention of 98.72 % after 200 cycles for the Zn/MnO2 full cell. This work provides a general electrolyte design strategy to suppress zinc dendrite growth and side reactions to achieve long-lifespan zinc metal anodes for aqueous zinc ion batteries by electrostatic shielding effect.
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Camellia fluviatilis is an important shrub producing edible seed oil, which is widely cultivated in South China. In this study, the complete chloroplast genome was sequenced and analyzed based on the Illumina HiSeq platform. The results showed that the complete chloroplast genome is 157,041 bp with 37.29% GC content, including a large single copy (LSC) region of 86,718 bp, a small single copy (SSC) region of 18,293 bp, and a pair of inverted repeats (IRs) regions of 26,015 bp. There are 128 genes in the chloroplast genome of C. fluviatilis, including 83 protein-coding genes, 8 ribosomal RNAs, and 37 transfer RNAs. Phylogenetic analysis revealed that C. fluviatilis is closely related to C. lanceoleosa, indicating that both belong to the Sect. Paracamellia Sealy.
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Great expectations have been held for the electrochemical splitting of water for producing hydrogen as a significant carbon-neutral technology aimed at solving the global energy crisis and greenhouse gas issues. However, the oxygen evolution reaction (OER) process must be energetically catalyzed over a long period at high output, leading to challenges for efficient and stable processing of electrodes for practical purposes. Here, we first prepared Fe-MOF nanosheet arrays on nickel foam via rare-earth erbium doping (Er0.4 Fe-MOF/NF) and applied them as OER electrocatalysts. The Er0.4 Fe-MOF/NF exhibited wonderful OER performance and could yield a 100 mA cm-2 current density at an overpotential of 248 mV with outstanding long-term electrochemical durability for at least 100 h. At large current densities of 500 and 1000 mA cm-2, overpotentials of only 297 mV and 326 mV were achieved, respectively, revealing its potential in industrial applications. The enhancement was attributed to the synergistic effects of the Fe and Er sites, with Er playing a supporting role in the engineering of the electronic states of the Fe sites to endow them with enhanced OER activity. Such a strategy of engineering the OER activity of Fe-MOF via rare-earth ion doping paves a new avenue to design other MOF catalysts for industrial OER applications.
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Camellia grijsii is an ornamental shrub with a floral aroma, which is widely cultivated and used for landscaping in China. To obtain the genetic information of C. grijsii, we have sequenced and assembled the complete chloroplast (cp) genome based on the Illumina Hiseq platform. The total genome size is 161,078 bp in length with 37.18% GC, which contains a large single copy (LSC, 84,645 bp) region, a small single copy (SSC, 15,772 bp) region, and a pair of inverted repeat (IRs, 30,330 bp) regions. It is composed of 81 protein-coding genes, 4 ribosomal RNAs, and 43 transfer RNAs. The cp genome of C. grijsii has also been compared with other species of Camellia, and the results showed that the C. grijsii and the C. grandbibracteata are closely related. This study provides the complete cp genome of C. grijsii and has an important reference value for the evolutionary analysis.
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Camellia grijsii 'zhenzhucha' is a variant cultivar from Camellia grijsii, which is also called Camellia grijsii 'juhuacha'.C. grijsii 'zhenzhucha' is an ornamental shrub with a floral aroma, and is oftenused in landscape. To provide genetic information for genetic research, we have sequenced and assembled the complete chloroplast (cp) genome of C. grijsii 'zhenzhucha' based on the Illumina Hiseq platform. The assembled complete cp genome of C. grijsii 'zhenzhucha' was 161,478 bp in length with 37.24% GC, including a large single-copy (LSC) region of 59,942 bp, a small single-copy (SSC) region of 17,294 bp, and a pair of inverted repeats (IRs) of 20,293 bp. The cp genome was annotated with 130 functional genes, consisting of 81 protein-coding genes, 45 transporter RNAs, and 4 ribosomal RNAs. To obtain the phylogeny relationship, the cp genome of C. grijsii 'zhenzhucha'has been compared with other Camellia species, and the results indicate that C. grijsii 'zhenzhucha' is closely related to C. grijsii. This study provides fundamental information of C. grijsii 'zhenzhucha' cp genome, and has an important reference value for the evolutionary analysis.