Carbonation of Ca/Mg minerals in industrial alkaline residues is a technology to sequester CO2 and reduce its emissions to the atmosphere. In this work, BSE-EDS were used to determine the mineral ...phase in steel slag; compositions of RO phase were identified and simulated. The carbon sequestration of steel slag was studied, and RO phase was activated by carbonation. Result shows that the amount of CO2 sequestered in steel slag and RO phase increases as carbonation time increases. Under autoclaving condition, the hydration ratio of MgO in RO phase was 20.10%. Through carbonation, up to 58.83% of MgO in RO phase can be converted into MgCO3, and the activation of RO phase by carbonation was manifested. The mechanical properties and volume stability of carbonated steel slag were improved, proving that the positive effect of carbonation on steel slag when applied in cement and cementitious materials.
Emotion recognition is an essential human ability critical for social functioning. It is widely assumed that identifying facial expression is the key to this, and models of emotion recognition have ...mainly focused on facial and bodily features in static, unnatural conditions. We developed a method called affective tracking to reveal and quantify the enormous contribution of visual context to affect (valence and arousal) perception. When characters’ faces and bodies were masked in silent videos, viewers inferred the affect of the invisible characters successfully and in high agreement based solely on visual context. We further show that the context is not only sufficient but also necessary to accurately perceive human affect over time, as it provides a substantial and unique contribution beyond the information available from face and body. Our method (which we have made publicly available) reveals that emotion recognition is, at its heart, an issue of context as much as it is about faces.
Edge computing (EC) has recently emerged as a promising paradigm that supports resource-hungry Internet of Things (IoT) applications with low latency services at the network edge. However, the ...limited capacity of computing resources at the edge server poses great challenges for scheduling application tasks. In this paper, a task scheduling problem is studied in the EC scenario, and multiple tasks are scheduled to virtual machines (VMs) configured at the edge server by maximizing the long-term task satisfaction degree (LTSD). The problem is formulated as a Markov decision process (MDP) for which the state, action, state transition, and reward are designed. We leverage deep reinforcement learning (DRL) to solve both time scheduling (i.e., the task execution order) and resource allocation (i.e., which VM the task is assigned to), considering the diversity of the tasks and the heterogeneity of available resources. A policy-based REINFORCE algorithm is proposed for the task scheduling problem, and a fully-connected neural network (FCN) is utilized to extract the features. Simulation results show that the proposed DRL-based task scheduling algorithm outperforms the existing methods in the literature in terms of the average task satisfaction degree and success ratio.
The objective of this study was to explore the impact of the coronavirus disease 2019 epidemic on ongoing and upcoming drug clinical trials. Qualitative semi-structured interviews were conducted with ...clinical trial staff and clinical trial subjects were surveyed by questionnaire in this study. The results of interviews and questionnaire showed that coronavirus disease 2019 pandemic has led to many changes in the implementation of drug clinical trials, including: a variety of meetings being held online webinars using various platforms, telemedicine and follow-up by video, A large number of deviations from protocol and losses of follow-up, delivery of clinical trial drugs by express, additional workload caused by screening for coronavirus, and anxiety of subjects. These results suggest that the coronavirus disease 2019 outbreak has hindered the progress and damaged the quality of clinical trials. The online meeting, remote follow-up, express delivery of drugs and remote monitoring in the epidemic environment can ensure the progress of clinical trials to a certain extent, but they cannot fully guarantee the quality as before.
•The indirect carbonation process of steel slag was studied.•The volume stability of steel slag was improved by indirect carbonation reaction.•The 28-day strength of CMs containing carbonated steel ...slag is improved.•Calcium carbonate fills pores and acts as the core of hydration products.
Attributable to the advantages of low cost, easy availability and high density, et al., steel slag has become the research focus of the cement concrete industry. In this paper, the indirect carbonation process of steel slag is studied, the cementitious materials are prepared by replacing part of cement with carbonated steel slag, the mechanical properties and volume stability of the cementitious materials were studied. The reasons for the influence of carbonated steel slag on the properties of cementitious materials are explored from the hydration properties. The results show that carbonation reaction can reduce the content of free calcium oxide in steel slag. The carbonation products are mainly calcite and are in the form of non-uniform particles and carbonation layer morphology. The volume stability of cementitious materials containing carbonated steel slag is improved effectively due to the consumption of the expansion phase. Although the silicate phase in steel slag will be carbonated, the calcium carbonate produced by carbonation fills the microcracks or pores of the cementitious materials, or becomes the core of the hydration product, which significantly improves the 28-day strength of the cementitious materials.
Molybdenum disulfide (MoS2) is a promising non-precious-metal catalyst, but its performance is limited by the density of active sites and poor electrical transport. Its metallic 1T phase possesses ...higher photoelectrocatalytic activity. Thus, how to efficiently increase the concentration of the 1T phase in the exfoliated two-dimensiaonal (2D) MoS2 nanosheets is an important premise. In this work, we propose a strategy to prepare a 2D heterostructure of MoS2 nanosheets using supercritical CO2-induced phase engineering to form metallic 1T-MoS2. Theoretical calculations and experimental results demonstrate that the introduced CO2 in the 2H-MoS2 host can prompt the transformation of partial 2H-MoS2 lattices into 1T-MoS2. Moreover, the electrical coupling and synergistic effect between 2H and 1T phases can greatly facilitate the efficient electron transfer from the active sites of MoS2, which significantly improves the photocatalytic performance.
A challenging but pressing task to design and synthesize novel, efficient, and robust pH‐universal hydrogen evolution reaction (HER) electrocatalysts for scalable and sustainable hydrogen production ...through electrochemical water splitting. Herein, we report a facile method to prepare an efficient and robust Ru‐M (M=Ni, Mn, Cu) bimetal nanoparticle and carbon quantum dot hybrid (RuM/CQDs) for pH‐universal HER. The RuNi/CQDs catalysts exhibit outstanding HER performance at all pH levels. The unexpected low overpotentials of 13, 58, and 18 mV shown by RuNi/CQDs allow a current density of 10 mA cm−2 in 1 m KOH, 0.5 m H2SO4, and 1 m PBS, respectively, for Ru loading at 5.93 μgRu cm−2. This performance is among the best catalytic activities reported for any platinum‐free electrocatalyst. Theoretical studies reveal that Ni doping results in a moderate weakening of the hydrogen bonding energy of nearby surface Ru atoms, which plays a critical role in improving the HER activity.
How low can Ru go: A scalable and general synthetic method for the preparation of transition‐metal‐doped RuM/carbon quantum dots (CQDs; M=Ni, Mn, Cu) has been developed through metal‐mediated CQD condensation and carbonization. The low‐ruthenium‐content RuM/CQD catalysts exhibit outstanding activity and stability in catalyzing hydrogen evolution at all pH values.
Even though transition‐metal phosphides (TMPs) have been developed as promising alternatives to Pt catalyst for the hydrogen evolution reaction (HER), further improvement of their performance ...requires fine regulation of the TMP sites related to their specific electronic structure. Herein, for the first time, boron (B)‐modulated electrocatalytic characteristics in CoP anchored on the carbon nanotubes (B‐CoP/CNT) with impressive HER activities over a wide pH range are reported. The HER performance surpasses commercial Pt/C in both neutral and alkaline media at large current density (>100 mA cm−2). A combined experimental and theoretical study identified that the B dopant could reform the local electronic configuration and atomic arrangement of bonded Co and adjacent P atoms, enhance the electrons’ delocalization capacity of Co atoms for high electrical conductivity, and optimize the free energy of H adsorption and H2 desorption on the active sites for better HER kinetics.
The importance of B in HERnest: Boron is introduced into CoP nanoparticles anchored on carbon nanotubes to form a robust pH‐universal hydrogen evolution reaction (HER) catalyst. The boron has a relatively low electronegativity and refines the electronic structure of the CoP catalytic sites, thus enhancing the electrical conductivity and optimizing the free energy of H adsorption, leading to improved electrocatalytic H2 production.
Necroptosis refers to a regulated form of cell death induced by a variety of stimuli. Although it has been implicated in the pathogenesis of many diseases, there is evidence to support that ...necroptosis is not purely a detrimental process. We propose that necroptosis is a "double-edged sword" in terms of physiology and pathology. On the one hand, necroptosis can trigger an uncontrolled inflammatory cascade response, resulting in severe tissue injury, disease chronicity, and even tumor progression. On the other hand, necroptosis functions as a host defense mechanism, exerting antipathogenic and antitumor effects through its powerful pro-inflammatory properties. Moreover, necroptosis plays an important role during both development and regeneration. Misestimation of the multifaceted features of necroptosis may influence the development of therapeutic approaches targeting necroptosis. In this review, we summarize current knowledge of the pathways involved in necroptosis as well as five important steps that determine its occurrence. The dual role of necroptosis in a variety of physiological and pathological conditions is also highlighted. Future studies and the development of therapeutic strategies targeting necroptosis should fully consider the complicated properties of this type of regulated cell death.
Rice husk-based hierarchical porous carbon (RHPC) has great promising applications in supercapacitors. Herein we systematically examined the formation mechanism of hierarchical porous structure of ...RHPC, tried to work out the intrinsic relationship of pore structure and the electrochemical performance. A method for separation of components in rice husk is proposed. It has been found that the pore structure in RHPC is closely related to different components in rice husk, and can be tuned by carbonization, desiliconization, and activation, shedding a light on the formation mechanism of the hierarchical porous structure in RHPC. The electrochemical performance of RHPC and the porous carbons made from three rice husk components has been correlated to their porous structure. The micropores function to provide a large number of adsorption sites for electrolyte ions, leading to high specific capacitance, while the mesopores coupled with the macropores function to provide fast transport channels for electrolyte ions, which play the key role for the excellent rate capability of RHPC. The stable skeleton structure with good conductivity ensures the superior cycling stability of RHPC.
Via a detailed component separation method, the pore source, the formation mechanism of hierarchical porous structure, and the structure-performance relationship of RHPC are determined. Display omitted
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