The development of aqueous zinc metal batteries (AZMBs) is significantly impeded by the poor cycle stability of Zn anodes due to the uncontrolled dendrite growth and low Coulombic efficiency (CE). ...Herein, for the first time, SeO2 additives are introduced into ZnSO4 electrolyte to enhance the stability of the Zn anode. According to the experimental results, the protective ZnSe layer is initially in‐situ formed on the Zn surface prior to the Zn plating, which acts as a shield for inhibiting the parasitic reactions and dendrite formation. Moreover, this additive strategy yields the unique characteristic of self‐healing for recovering the cracks in the consequence of huge volume change, ensuring the durability of ZnSe layer. Consequently, Zn|Zn symmetric cell using SeO2 additive delivers an enhanced cumulative plated capacity of 2.1 Ah cm−2 under practical test conditions, which far exceeds the previously reported works. Meanwhile, the average CE of 99.6% for 250 cycles is also demonstrated in Zn|Cu half cells with the presence of the SeO2 additive. In addition, the positive effect of the SeO2 additive is further illustrated in the Zn‐MnO2 full cells with a limited Zn.
SeO2 additive is first introduced as solid electrolyte interphase (SEI)−forming agent for stabilizing Zn anodes. With the addition of SeO2, Zn symmetric cells display a high cumulative plated capacity of 2.1 Ah cm−2 and a high average Coulombic efficiency of 99.6% under harsh test conditions (2 mA cm−2, 2 mAh cm−2).
•Magnetite nanoparticle was fabricated through a simple routine to activate persulfate.•Hydroxyl radicals dominated the degradation process at acidic condition.•Both free and surface bound radicals ...existed in the oxidation system.•Transformation of piperazinyl ring was the primary degradation pathway.
Uniform magnetite nanoparticles (MNP) were prepared through a facile hydrothermal routine and subjected to the heterogeneous activation of persulfate (PS) to degrade norfloxacin (NOR). The degradation efficiency reached 90% within 60min (the concentration of NOR and PS was 15μM and 1mM, respectively; dose of MNP: 0.3gL−1; pH: 4.0). However, it was greatly inhibited with the increase of pH, especially at basic condition (pH0=9.0). This was probably due to the precipitation of the ferrous ions leached from the surface of MNP. In addition, hydroxyl radical was found to dominate the degradation process at acidic condition while both sulfate and hydroxyl radicals contributed to the degradation at neutral condition. Except the leached form, the structural ferrous ion on the surface of MNP also participated in the activation process through the redox reactions, as illustrated by the X-ray photoelectron spectroscopy (XPS) analysis. Finally, four degradation pathways were tentatively proposed based on the identified intermediates and the transformation of piperazinyl ring seemed to be the primary one.
A catalyst‐ and supporting electrolyte‐free method for electrochemical dehydrogenative C−S bond formation in continuous flow has been developed. A broad range of N‐arylthioamides have been converted ...to the corresponding benzothiazoles in good to excellent yields and with high current efficiencies. This transformation is achieved using only electricity and laboratory grade solvent, avoiding degassing or the use of inert atmosphere. This work highlights three advantages of electrochemistry in flow, which is (i) a supporting electrolyte‐free reaction, (ii) an easy scale‐up of the reaction without the need for a larger reactor and, (iii) the important and effective impact of having a good mixing of the reaction mixture, which can be achieved effectively with the use of flow systems. This clearly improves the reported methods for the synthesis of benzothiazoles.
No catalyst and no supporting electrolyte are needed for the formation of benzothiazoles from N‐arylthioamides. Electrons and a flow reactor for electrochemistry are sufficient.
The geyser phenomenon seriously threatens the safe operation of deep tunnel drainage systems and drop shaft structural safety. To simulate the geyser process in a baffle-drop shaft, a 1:50 scale ...model test system was used to research the response relationship between the geyser mechanism and test parameters such as water depth, inlet pressure, and inlet volume. The results show that the pressure in a baffle-drop shaft fluctuates sharply during the geyser process. This is caused by the release of a high-pressure air mass, and high-speed movement of the air-water mixture causes a local pressure imbalance in the drop shaft. A prediction formula for the maximum geyser height of a baffle-drop shaft was established by a multiple linear regression model. Geyser occurrence conditions for the baffle-drop shaft were proposed combined with the response relationship between different influence variables and geyser intensity. Except for the inlet pressure, submerged state of the baffles, and measured location, the hydrodynamic load on the bottom of the baffles is also related to the randomness of the air-water mixture jetted on the baffle bottom. The maximum hydrodynamic load on the baffle bottom during the geyser is 10 times the hydrodynamic load on the baffle surface under normal discharge conditions. This research provides a theoretical reference for the structural design and safe operation of baffle-drop shafts.
Regulating the electrical double layer (EDL) structure
via
electrolyte additives is a promising strategy to improve the cycling stability of Zn anodes, but there are no general strategies that can be ...used to rationally design EDL regulators for upgrading the Zn protection performance. Herein, by screening 15 solvent additives as EDL regulators, we reveal that the solid electrolyte interphase (SEI) capability of EDL regulators, instead of other parameters like the donor number, adsorption energy, and dielectric constant, predominately controls the cycling stability of Zn anodes. Specifically, the SEI capability of EDL regulators endows the Zn surface with a uniform and dense SEI layer, which physically isolates Zn anodes from electrolytes and induces dendrite-free Zn deposition. As a model electrolyte, 2M ZnSO
4
solution with 0.5 vol% sulfolane enables Zn anodes to deliver high Zn plating/stripping reversibility under harsh test conditions. The compatibility of this designed electrolyte with V
2
O
5
and MnO
2
cathodes is also demonstrated at low N/P ratios of 5.5 and 3.2, respectively.
Combined with experimental and theoretical studies, we revealed a critical criterion that gives priority to the SEI-forming capability of additives for developing effective EDL structure regulators.
Circular RNAs (circRNAs) represent a type of endogenous noncoding RNAs that are generated by back-splicing events and favor repetitive sequences. Recent studies have reported that cancer-associated ...chromosomal translocations could juxtapose distant complementary repetitive intronic sequences, resulting in the aberrant formation of circRNAs. However, among the reported fusion genes, only a small number of circRNAs were found to originate from fusion regions during gene translocation. We question if circRNAs could also originate from fusion partners during gene translocation.
Firstly, we designed divergent primers for qRT-PCR to identify a circRNA circAF4 in AF4 gene and investigated the expression pattern in different types of leukemia samples. Secondly, we designed two small interfering RNAs specially targeting the back-spliced junction point of circAF4 for functional studies. CCK8 cell proliferation and cell cycle assay were performed, and a NOD-SCID mouse model was used to investigate the contribution of circAF4 in leukemogenesis. Finally, luciferase reporter assay, AGO2 RNA immunoprecipitation (RIP), and RNA Fluorescent in Situ Hybridization (FISH) were performed to confirm the relationship of miR-128-3p, circAF4, and MLL-AF4 expression.
We discovered a circRNA, named circAF4, originating from the AF4 gene, a partner of the MLL fusion gene in MLL-AF4 leukemia. We showed that circAF4 plays an oncogenic role in MLL-AF4 leukemia and promotes leukemogenesis in vitro and in vivo. More importantly, knockdown of circAF4 increases the leukemic cell apoptosis rate in MLL-AF4 leukemia cells, while no effect was observed in leukemia cells that do not carry the MLL-AF4 translocation. Mechanically, circAF4 can act as a miR-128-3p sponge, thereby releasing its inhibition on MLL-AF4 expression. We finally analyzed most of the MLL fusion genes loci and found that a number of circRNAs could originate from these partners, suggesting the potential roles of fusion gene partner-originating circRNAs (named as FP-circRNAs) in leukemia with chromosomal translocations.
Our findings demonstrate that the abnormal elevated expression of circAF4 regulates the cell growth via the circAF4/miR-128-3p/MLL-AF4 axis, which could contribute to leukemogenesis, suggesting that circAF4 may be a novel therapeutic target of MLL-AF4 leukemia.
The solid electrolyte interphase (SEI)‐forming additives strategy is of great significance for improving the cycle stability of zinc (Zn) anodes. Although various additives have been reported, the ...relationship between their molecular structures and SEI chemistries is poorly understood. Herein, a molecular design principle for sulfonamide‐containing additives that endow Zn anodes with a robust SEI layer is proposed. The incorporation of the benzene ring and amino group (−NH2) leads to high adsorption energy, low lowest unoccupied molecular orbital lowest unoccupied molecular orbital (LUMO), and a small highest occupied molecular orbital‐LUMO (HOMO‐LUMO) gap, facilitating the reduction process of sulfanilamide (SA) additives. Coupled with SA/ZnSO4 electrolytes, Zn|Zn symmetric cells deliver an ultralong cycle life of 4800 h (200 days) at 2 mA cm−2 and 2 mAh cm−2. Additionally, a high cumulative plated capacity (CPC) of 6000 mAh cm−2 and 2700 mAh cm−2 is also achieved at a capacity per cycle of 10 mAh cm−2 and 30 mAh cm−2, respectively. More importantly, the versatility of SA additives is also demonstrated in Zn‐V2O5, Zn‐I2, and Zn‐MnO2 full cells at a low N/P ratio (the theoretical capacity ratio between the negative and positive electrode) of 5.3, 8.3, and 4.5, respectively. This molecular structure strategy provides a promising path to develop effective SEI‐forming additives.
This study provides the solid electrolyte interphase forming additive design criteria for Zn metal batteries by combined theoretical calculations and experiments. With the optimized sulfanilamide additives, Zn symmetric cells display an ultralong cycle life of 4800 h (200 days) and a high average CE of 99.3% under harsh test conditions (10 mA cm−2 and 10 mAh cm−2).
Five new zero-dimensional hybrid manganese halides based on discrete MnCl
4
2−
tetrahedrons were prepared and used as highly efficient green-light emitters. Through rational management of organic ...cations to tailor the Mn Mn separation distances between neighboring MnCl
4
2−
tetrahedrons, the photoluminescence quantum yield increased significantly from 7.98% to 81.11%.
Five new zero-dimensional hybrid manganese halides based on discrete MnCl
4
2−
tetrahedrons were prepared and used as highly efficient green-light emitters.
Species of Pomacea, commonly known as apple snails, are native to South America, and have become widely distributed agricultural and environmental pests in southern China since their introduction in ...the 1980s. However, only since 2010 have researchers recognized that at least two species, P. canaliculata and P. maculata, are present in China. Although impacts of apple snails have been extensively documented, confusion still persists regarding current distributions and origin of the species in China. To resolve this confusion, we used phylogenetic and phylogeographic methods to analyze 1464 mitochondrial COI sequences, including 349 new sequences from samples collected in southern China and 1115 publicly available sequences from snails collected in the native and introduced ranges. Pomacea canaliculata was found at all sampled localities, while P. maculata was found at only five sampled localities in the Sichuan basin and Zhejiang province. Our data indicate that Chinese populations of P. canaliculata share an Argentinian origin, consistent with multiple introductions of this species elsewhere in Asia. In addition, just a single lineage of P. maculata is established in China, which shares with populations in Brazil.
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