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Capacitive deionization (CDI) is considered one of the most promising desalination technologies for obtaining fresh water from saline water. In this work, we synthesized a hollow ...core–shell Co-MOF@Fe/Co-LDH (Co-Fe-LDH) material by developing a strategy to simultaneously grow Co/Fe-LDH on the surface of a Co-MOF precursor in situ. Owing to the increase in the specific surface area of the hollow structure and the Faradaic process of a layered double hydroxide (LDH), the Co-Fe-LDH material exhibits high electrical double layer (EDL) capacitance and pseudocapacitance, which significantly improves the salt adsorption of the material during CDI (34.2 mg/g in a 600 mg/L NaCl solution at 1.2 V). The adsorption for NaCl in this work is approximately 2.5 times the maximum salt adsorption capacity (SAC) of LDH materials applied in nonmembrane CDI (NMCDI). This work may provide a promising model for the application of hollow LDH materials that exhibit pseudocapacitance in CDI.
When lithium-ion batteries age with cycling, the battery capacity decreases and the resistance increases. The aging mechanism of different types of lithium-ion batteries differs. The loss of lithium ...inventory, loss of active material, and the increase in resistance may result in battery aging. Generally, analysis of the battery aging mechanism requires dismantling of batteries and using methods such as X-ray diffraction and scanning electron microscopy. These methods may permanently damage the battery. Therefore, the methods are inappropriate for the battery management system (BMS) in an electric vehicle. The constant current charging curves while charging the battery could be used to get the incremental capacity and differential voltage curves for identifying the aging mechanism; the battery state-of-health can then be estimated. This method can be potentially used in the BMS for online diagnostic and prognostic services. The genetic algorithm could be used to quantitatively analyze the battery aging offline. And the membership function could be used for onboard aging mechanism identification.
•Aging mechanisms of five different battery types are analyzed by incremental capacity curve.•Aging mechanisms of LFP batteries are analyzed by charging voltage curve reproduction.•On-line identification of aging mechanism and SOH estimation of LFP batteries are discussed.
The occurrence and fate of six phthalates: dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), bis (2-ethylhexyl) phthalate (DEHP) and ...di-n-octyl phthalate (DOP) were investigated as phthalates passed through three full-scale wastewater treatment plants (WWTPs) with different treatment processes, and ultimately into the recipient Songhua River water in Harbin (China). The six phthalates were detected in the majority of aqueous and solid samples, with DEHP being the most abundant compound. The overall removal efficiency of ΣPAEs in the Cyclic Activated Sludge Technology (CAST) process was over 72%, while both the A/O and A/A/O processes achieved approximately 30% removal. The better performance of the CAST process relative to the Anoxic/Oxic (A/O) and Anaerobic/Anoxic/Oxic (A/A/O) processes was attributed to the indoor-conditions of the CAST plants, which effectively maintained the temperature of the treatment system. The fate of PAEs within two different types of WWTPs (CAST and A/A/O) were assessed qualitatively using mass balances. The results suggested that PAEs removal resulted from both biotransformation and adsorption, of which the former was particularly significant in the CAST process, while the latter was more significant in the A/A/O process. Substantial levels of several PAEs were detected in the Songhua River, especially downstream of the WWTPs, which means that the discharge from WWTPs has a strong impact on the water quality of the Songhua River during cold winter conditions.
Abstract
The development of efficient catalysts for Fischer–Tropsch (FT) synthesis, a core reaction in the utilization of non-petroleum carbon resources to supply energy and chemicals, has attracted ...much recent attention. ε-Iron carbide (ε-Fe
2
C) was proposed as the most active iron phase for FT synthesis, but this phase is generally unstable under realistic FT reaction conditions (> 523 K). Here, we succeed in stabilizing pure-phase ε-Fe
2
C nanocrystals by confining them into graphene layers and obtain an iron-time yield of 1258 μmol
CO
g
Fe
−1
s
−1
under realistic FT synthesis conditions, one order of magnitude higher than that of the conventional carbon-supported Fe catalyst. The ε-Fe
2
C@graphene catalyst is stable at least for 400 h under high-temperature conditions. Density functional theory (DFT) calculations reveal the feasible formation of ε-Fe
2
C by carburization of α-Fe precursor through interfacial interactions of ε-Fe
2
C@graphene. This work provides a promising strategy to design highly active and stable Fe-based FT catalysts.
Herein, we report a deep‐red TADF emitter pCNQ–TPA, composed of quinoxaline‐5,8‐dicarbonitrile (pCNQ) acceptor and triphenylamine (TPA) donor. pCNQ–TPA supported its OLED with desired CIE coordinates ...of (0.69, 0.31) and the record maximum external quantum efficiency of 30.3 %, which is the best red TADF diode with Rec.2020 gamut for UHDTV. It is showed that through tuning pCNQ–TPA doping concentration, intra‐ and inter‐molecular charge transfer are balanced to synchronously improve emission color saturation and TADF radiation, and remedy aggregation‐induced quenching, rendering photoluminescence quantum yield (PLQY) reaching 90 % for deep‐red emission peaked at ≈690 nm. Quasi‐planar structure further endows pCNQ–TPA with an improved horizontal ratio of emitting dipole orientation, which increases light out‐coupling ratio to 0.34 for achieving the state‐of‐the‐art device efficiencies.
A deep‐red TADF emitter pCNQ–TPA for UHD display was demonstrated, which realized the desired chromaticity matching rec.2020 standard and the record external quantum efficiency beyond 30 %. It is showed that its quasi‐planar structure not only improves horizontal ratio of emitting dipole orientation for out‐coupling enhancement, but also balances the intra‐ and inter‐molecular charge transfer for radiation facilitation and quenching suppression.
•A review about corrosion mechanism of rebars and relevant morning or detection devices.•A revised theoretical model was proposed.•A novel monitoring system was introduced.
It is widely acknowledged ...that corrosion of reinforced bars is a tremendous challenge against durability performance of reinforced concrete (RC) structures, especially under aggressive environment. Correspondingly, corrosion mechanism has been in-depth investigated all over the world, moreover, amounts of monitoring or detection apparatus have been developed in order to obtain or visualize the damage degree of corroded reinforcements inside concrete, which cannot be recognized by naked eyes. This paper aims to make a short review about corrosion mechanism as well as relevant morning or detection devices based on various physical backgrounds, which include optics, electromagnetism, acoustic, X-ray CT, radarand others. The result shows that much more studies are focusing on the development or upgrading of novel monitoring equipment against reinforcement corrosion, and a revised theoretical model is also putted forward based on non-uniform corrosion type for judging the corrosion-triggered cracks more accurately. Moreover, a suggestive idea has been raised about establishing an intelligent monitoring system which includes novel sensors, data collection and transmission device, and also evaluation procedure as well.
•A frequency-based method to determine flood threshold by results of distributed model.•Using binary classification to derive rainfall threshold for flood warning.•Relationship between rainfall ...threshold and soil moisture state varies with climate.•Applicability of the method to both gauged and ungauged catchments.
Flash flooding is one of the most common natural hazards in China, particularly in mountainous areas, and usually causes heavy damage and casualties. However, the forecasting of flash flooding in mountainous regions remains challenging because of the short response time and limited monitoring capacity. This paper aims to establish a strategy for flash flood warnings in mountainous ungauged catchments across humid, semi-humid and semi-arid regions of China. First, we implement a geomorphology-based hydrological model (GBHM) in four mountainous catchments with drainage areas that ranges from 493 to 1601km2. The results show that the GBHM can simulate flash floods appropriately in these four study catchments. We propose a method to determine the rainfall threshold for flood warning by using frequency analysis and binary classification based on long-term GBHM simulations that are forced by historical rainfall data to create a practically easy and straightforward approach for flash flood forecasting in ungauged mountainous catchments with drainage areas from tens to hundreds of square kilometers. The results show that the rainfall threshold value decreases significantly with increasing antecedent soil moisture in humid regions, while this value decreases slightly with increasing soil moisture in semi-humid and semi-arid regions. We also find that accumulative rainfall over a certain time span (or rainfall over a long time span) is an appropriate threshold for flash flood warnings in humid regions because the runoff is dominated by excess saturation. However, the rainfall intensity (or rainfall over a short time span) is more suitable in semi-humid and semi-arid regions because excess infiltration dominates the runoff in these regions. We conduct a comprehensive evaluation of the rainfall threshold and find that the proposed method produces reasonably accurate flash flood warnings in the study catchments. An evaluation of the performance at uncalibrated interior points in the four gauged catchments provides results that are indicative of the expected performance at ungauged locations. We also find that insufficient historical data lengths (13years with a 5-year flood return period in this study) may introduce uncertainty in the estimation of the flood/rainfall threshold because of the small number of flood events that are used in binary classification. A data sample that contains enough flood events (10 events suggested in the present study) that exceed the threshold value is necessary to obtain acceptable results from binary classification.
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that can cause gastrointestinal ulcers by affecting dopamine levels. Therefore, MPTP has been considered a toxic substance that ...causes gastric ulcer disease in experimental animals. In this study, tree shrews were used as the animal model of gastric mucosa injury, and MPTP was intraperitoneally injected at a lower MPTP dosage 2 mg/kg/day for 13 weeks, while tree shrews were not injected as the control group. Under the light microscope, local congestion or diffuse bleeding points of gastric mucosa and multiple redness and swelling bleeding symptoms on the inner wall were observed in the treatment group, as well as immune cell infiltration was found in HE staining, but no such phenomenon was observed in the control group. In order to explore the molecular basis of changes in MPTP induced gastric mucosa injury, the transcriptome and proteome data of gastric mucosa were analyzed. We observed significant differences in mRNA and protein expression levels under the influence of MPTP. The changes in mRNA and proteins are related to increased immune infiltration, cellular processes and angiogenesis. More differentially expressed genes play a role in immune function, especially the candidate genes RPL4 and ANXA1 with significant signal and core role. There are also differentially expressed genes that play a role in mucosal injury and shedding, especially candidate genes GAST and DDC with certain signaling and corresponding functions. Understanding the factors and molecular basis that affect the expression of related genes is crucial for coping with Emotionality gastric mucosa injury disease and developing new treatment methods to establish the ability to resist disease.
Information relay at the molecular level is an essential phenomenon in numerous chemical and biological processes, such as intricate signaling cascades. One key challenge in synthetic molecular ...self-assembly is to construct artificial structures that imitate these complex behaviors in controllable systems. We demonstrated prescribed, long-range information relay in an artificial molecular array assembled from modular DNA structural units. The dynamic DNA molecular array exhibits transformations with programmable initiation, propagation, and regulation. The transformation of the array can be initiated at selected units and then propagated, without addition of extra triggers, to neighboring units and eventually the entire array. The specific information pathways by which this transformation occurs can be controlled by altering the design of individual units and the arrays.
Five‐membered N‐heterocycles play an important role in organic synthesis and material chemistry, as they are widespread through pharmaceutical molecules and natural products. Chemists have developed ...many synthetic strategies for constructing five‐membered N‐heterocycles from N‐centered radicals, but the availability of mild and green methods for these transformations is still limited. The cyclization of visible‐light‐generated N‐centered radicals with alkenes has emerged as a powerful tool to enable these chemical transformations in recent years. Through chosen representative examples, the significant developments in this promising field were outlined, including the selection of catalysts, substrate scope, mechanistic understanding (especially density functional theory calculations), and applications. The contents of this Minireview are categorized by intramolecular cyclization and intermolecular N‐centered radical addition/cyclization reactions.
N‐heterocycles: The cyclization of visible‐light‐generated N‐centered radicals with alkenes has emerged as a powerful tool for constructing five‐membered N‐heterocycles. Through chosen representative examples, the significant developments in this promising field are outlined, including the selection of catalysts, substrate scope, mechanistic understanding (especially density functional theory calculations), and applications.
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