High gravimetric, areal and volumetric capacities together with long lifetime are key indexes for the applications of lithium–sulfur (Li‐S) batteries in compact space. The sulfur host materials play ...pivotal roles in the practical deployment. Herein, one type of new heterostructure nanosheets composed of cobalt boride (CoB) on nitrogen, boron‐codoped porous carbon (NBC), which is constructed through molten salt‐assisted strategy using ZIF‐67‐encapsulated ZIF‐8 as precursors is reported on. Benefiting from strong interfacial electronic interactions between binary sulfiphilic CoB and porous NBC, the CoB/NBC‐S electrode exhibits the excellent cycling stability with low average capacity decay of 0.013% in ultralong 1500 cycles at high rate of 5 C. Remarkably, the electrode with high sulfur content of 82 wt% and high sulfur loading of 5.8 mg cm−2 delivers gravimetric capacity of 1309 mA h g−1, areal capacity of 7.59 mA h cm−2, and volumetric capacity of 1355 mA h cm−3 at 0.1 C. The favorable electrochemical performance can rival with the state‐of‐the‐art of those in the reported nanosheets‐based sulfur cathodes. This study provides new methodology for the design of heterostructure nanosheets of metal borides to achieve energy density and longevity of Li‐S batteries.
A type of new heterostructure nanosheets composed of binary sulfiphilic cobalt boride (CoB) on nitrogen, boron‐codoped porous carbon (NBC), is fabricated through a molten salt‐assisted strategy using ZIF‐67‐encapsulated ZIF‐8 as precursors. Strong interfacial electronic interactions between CoB and NBC endow the CoB/NBC‐S electrode with high gravimetric/areal/volumetric capacities and long lifetime in lithium–sulfur batteries.
In the process of oilfield exploitation, the water-flooded layer in the Minghuazhen Formation cannot be accurately identified, which has a great impact on the oilfield exploitation efficiency. If the ...water-flooded layer marker in the Minghuazhen Formation cannot be fundamentally defined, the oilfield may not be able to carry out normal exploitation operation. Based ON this, THIS PAPER expounds the basic characteristics of oil accumulation in the water-flooded layer of Minghuazhen Formation, puts forward the characteristics of the water-flooded layer, and analyzes the factors of low resistance for reference.
The coronavirus disease 2019 (COVID-19) has become a worldwide public health crisis. At present, there are no effective antiviral drugs to treat COVID-19. Although some vaccines have been developed, ...late-stage clinical trials that allow licensure by regulatory agencies are still needed. Previous reports have indicated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and SARS-CoV are highly homologous and both use angiotensin-converting enzyme 2 (ACE2) as the receptor to enter cells, and SARS-CoV infection reduces the ACE2 expression in the lung. Therefore, the analysis of genes co-expressed with ACE2 in the lung may uncover the underlying mechanism of COVID-19. Finally, we used the Connectivity map (Cmap) database to search for candidate drugs using transcriptome profiles of patients with COVID-19.
Based on the differentially expressed genes (DEGs), indicated by the expression of RNAs isolated from bronchoalveolar lavage fluid (BALF) cells of patients with COVID-19, we performed functional enrichment analysis and hub gene cluster analysis. Furthermore, we identified genes co-expressed with ACE2 in healthy lung samples and analyzed the significant genes. Additionally, to identify several candidate drugs for the treatment of COVID-19, we queried Cmap using DEGs and genes co-expressed with ACE2.
The up-regulated genes in the BALF cells of patients with COVID-19 are related to viral mRNA translation. The down-regulated genes are related to immune response functions. Genes positively correlated with ACE2 are related to immune defense and those negatively correlated are enriched in synaptic transmission functions. The results reflected prosperous viral proliferation and immune dysfunction in patients. Furthermore, ACE2 may not only mediate viral entrance, but also play an important role in immune defense. By using Cmap with transcriptome profiles of patients with COVID-19, we identified candidate drugs for the treatment of COVID-19, such as amantadine and acyclovir.
A semi-quantitative, macroscopic, phenomenon-based, thermo-elastic–plastic model was developed to predict the final plastic strains of single crystal nickel-based superalloys by considering their ...orthotropic mechanical properties. Various cases were considered and simulated to investigate the basic factors that influence the final plasticity. Thermo-mechanical numerical analysis was conducted to predict the recrystallization sites of simplified cored rods, with the results in good agreement with the experimental results. These hollowed rods with thin walls showed an increased propensity for recrystallization. The geometric features, especially stress concentration sites, are more significant to the induced plasticity than the material's orientation or shell/core materials. This paper also attempts to provide useful suggestions, such as introducing filets, to avoid causing plastic strains during the casting process that induce recrystallization.
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•A novel defective hierarchical micro-sorbent has been manufactured through Bubble-induced self-assembly synthesis route.•The as-synthesized super-sorbent with hierarchical structure ...demonstrates sufficient strengths in microstructure.•The BMS-4 super-sorbent exhibits the best adsorption properties and exceptional recovery and recycling performance for Congo red.•It is illustrated that the amino protonation, oxygen vacancy capture and BMS-4/CR–SO3+–NH3 mechanism enhances adsorption for CR dyes.
To cope with the increasingly urgent environmental issue and provide promising alternative adsorbents, the synergistic preparation route of dissolution and bubble-induced self-assembly was firstly exploited to guide the reconstruction process of a defective hierarchical porous boehmite-microspheres (BMS) adsorbent in a favorable direction to improve the CR adsorption capacity using aluminium hydroxide industrial waste as raw materials. Multiple non-in-situ physicochemical characterization instruments demonstrate that BMS-4 adsorbent possesses abundant coordinatively unsaturated Al–species, large specific surface area, high porosity, oxygen vacancies and oxygen-containing groups, which promote the maximum adsorption capacities for CR up to 6805.08 ± 5.4 mg g−1. Moreover, the Pseudo-second order model and the Langmuir model are more suitable for describing the behavior of CR adsorption, which proves it is more inclined to be monolayer adsorption and there is no chemical reaction between CR and adsorbent. More importantly, it can be practiced in eight cycles of adsorption tests, achieving ultra-high stability for over 94.46 % of the original adsorption capacity. Combined with density-functional theory (DFT) calculations and experimental results, it is illustrated that the amino protonation is responsible for the additional enhancement of CR adsorption, in addition, oxygen vacancy capture and BMS-4/CR–SO3+–NH3 mechanism for enhanced adsorption of dyes is proposed, both of which show that bubble-induced self-assembly provides a promising route for the preparation of high-performance adsorbents.
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•A CA approach was utilized to predict recrystallization of an Nickel-based SX superalloy.•The activation energy in IDRs is much higher than that in DAs.•The activation energy ...includes both the diffusion effect and the phase dissolution effect.•Many small grains will nucleate and be left in IDRs.
Recrystallization (RX) in an as-cast single crystal (SX) nickel-based superalloy was investigated using simulation and experiments. One cellular automaton (CA) method was proposed to predict RX microstructure of SX superalloys. The stored energy was obtained using one macroscopic phenomenon-based elastic–plastic model in this research, and the orthotropic mechanical properties were taken into account. Kinetics parameters were used on the basis of physical fundamentals, and different values were employed in the dendritic arms and interdendritic regions. In order to validate the simulation model, heat treatments under inert atmosphere were conducted on compressed cylinder samples to induce RX. The RX microstructures on the middle section perpendicular to the cylinder axis were observed using EBSD technique. Both simulation and experiments show that the kinetics of recrystallization were significantly different in dendritic arms and interdendritic regions, and simulated microstructure agrees well with experimental. The proposed model in this research can predict the kinetics, microstructural evolution during recrystallization of as-cast SX superalloys.
Real-time functional magnetic resonance imaging neurofeedback (rtfMRI-NF) is a prospective tool to enhance the emotion regulation capability of participants and to alleviate their emotional ...disorders. The hippocampus is a key brain region in the emotional brain network and plays a significant role in social cognition and emotion processing in the brain. However, few studies have focused on the emotion NF of the hippocampus. This study investigated the feasibility of NF training of healthy participants to self-regulate the activation of the hippocampus and assessed the effect of rtfMRI-NF on the hippocampus before and after training. Twenty-six right-handed healthy volunteers were randomly assigned to the experimental group receiving hippocampal rtfMRI-NF (
= 13) and the control group (CG) receiving rtfMRI-NF from the intraparietal sulcus rtfMRI-NF (
= 13) and completed a total of four NF runs. The hippocampus and the intraparietal sulcus were defined based on the Montreal Neurological Institute (MNI) standard template, and NF signal was measured as a percent signal change relative to the baseline obtained by averaging the fMRI signal for the preceding 20 s long rest block. NF signal (percent signal change) was updated every 2 s and was displayed on the screen. The amplitude of low-frequency fluctuation and regional homogeneity values was calculated to evaluate the effects of NF on spontaneous neural activity in resting-state fMRI. A standard general linear model (GLM) analysis was separately conducted for each fMRI NF run. Results showed that the activation of hippocampus increased after four NF training runs. The hippocampal activity of the experiment group participants was higher than that of the CG. They also showed elevated hippocampal activity and the greater amygdala-hippocampus connectivity. The anterior temporal lobe, parahippocampal gyrus, hippocampus, and amygdala of brain regions associated with emotional processing were activated during training. We presented a proof-of-concept study using rtfMRI-NF for hippocampus up-regulation in the recall of positive autobiographical memories. The current study may provide a new method to regulate our emotions and can potentially be applied to the clinical treatment of emotional disorders.
Calcific aortic valve disease (CAVD) is characterized by a fibrocalcific process. The regulatory mechanisms that drive the fibrotic response in the aortic valve (AV) are poorly understood. Long ...noncoding RNAs derived from super-enhancers (lncRNA-SE) control gene expression and cell fate. Herein, multidimensional profiling including chromatin immunoprecipitation and sequencing, transposase-accessible chromatin sequencing, genome-wide 3D chromatin contacts of enhancer-promoter identified LINC01013 as an overexpressed lncRNA-SE during CAVD. LINC01013 is within a loop anchor, which has contact with the promoter of CCN2 (CTGF) located at ~180 kb upstream. Investigation showed that LINC01013 acts as a decoy factor for the negative transcription elongation factor E (NELF-E), whereby it controls the expression of CCN2. LINC01013-CCN2 is part of a transforming growth factor beta 1 (TGFB1) network and exerts a control over fibrogenesis. These findings illustrate a novel mechanism whereby a dysregulated lncRNA-SE controls, through a looping process, the expression of CCN2 and fibrogenesis of the AV.
Red mud (RM), a hazardous solid waste generated in the alumina production process, of which the mineral composition is mainly hematite, is unable to be applied directly in the cement industry due to ...its high alkalinity. With the rise of geopolymers, RM-based grouting materials play an essential role in disaster prevention and underground engineering. To adequately reduce the land-based stockpiling of solid wastes, ultrafine calcium oxide, red mud, and slag were utilized as the main raw materials to prepare geopolymers, the C-R-S (calcium oxide–red mud–slag) grouting cementitious materials. The direct impact of red mud addition on the setting time, fluidity, water secretion, mechanical properties, and rheological properties of C-R-S were also investigated. In addition, a scanning electron microscope (SEM), X-ray diffraction (XRD), three-dimensional CT (3D-CT), Fourier transform infrared spectroscopy (FT-IR), and other characterization techniques were used to analyze the microstructure and polymerization mechanism. The related results reveal that the increase in red mud addition leads to an enhanced setting time, and the C-R-S-40 grouting cementitious material (40% red mud addition) exhibits the best fluidity of 27.5 cm, the lowest water secretion rate of 5.7%, and a high mechanical strength of 57.7 MPa. The C-R-S polymer grout conforms to the Herschel–Bulkley model, and the fitted value of R2 is above 0.99. All analyses confirm that the preparation process of C-R-S grouting cementitious material not only substantially improves the utilization rate of red mud, but also provides a theoretical basis for the high-volume application of red mud in the field of grouting.
The Mg2+ and Ca2+ exchange properties in the meso-zeolite LTA were investigated. These meso-zeolite materials with intracrystalline mesopores ca. 3nm were prepared using organic functioned fumed ...silica as silica source. The Dual-site Langmuir (D-L) expression appropriately describes the equilibrium data for the Ca2+ and Mg2+ exchange. The fitting results with D-L model suggest that two kinds of ion-exchange sites in the meso-zeolites exist, one in the part of intrinsic micropore structure (internal surface area) and the other one in the part of established mesopore structure (external surface area). The latter site has lower enthalpy values of Ca2+ or Mg2+ exchanges than the former one. Ca2+ or Mg2+ exchange kinetics is conducted at 273K, 288K and 308K. The results show the emergence of mesopores lowering the activation energy of ion exchange and accelerating Mg2+ exchange extremely in the materials. The diffusion rate of hydrated Mg2+ in the meso-zeolite LTA increases by 17.5 times, higher than that of conventional LTA at 273K. And the meso-zeolite LTA possesses large Mg2+ competitive ability in a solution containing Ca2+ and Mg2+. These properties make the meso-zeolite LTA a suitable material which could be used effectively in hard water softening and detergent building for Mg2+ removing.
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•Mg2+ and Ca2+ competitive exchange properties in the meso-zeolite LTA•There are two kinds of ion-exchange sites in the meso-zeolites.•The lower activation energy and higher rate of ion-exchange in mesopore structures•The Dual-site Langmuir isotherms for the equilibrium of Ca2+ and Mg2+ exchange
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