Here, a Sn–C composite material prepared from bulk precursors (tin metal, graphite, and melamine) using ball milling and annealing is reported. The composite (58 wt% Sn and 42 wt% N‐doped carbon) ...shows a capacity up to 445 mAh gSn+C−1 and an excellent cycle life (1000 cycles). For the graphite, the ball milling leads to graphene nanoplatelets (GnP) for which the storage mechanism changes from solvent co‐intercalation to conventional intercalation. The final composite (Sn at nitrogen‐doped graphite nanoplatelets (SnNGnP)) is obtained by combining the GnPs with Sn and melamine as the nitrogen source. Rate‐dependent measurements and in situ X‐ray diffraction are used to study the asymmetric storage behavior of Sn, which shows a more sloping potential profile during sodiation and more defined steps during desodiation. The disappearance of two redox plateaus during desodiation is linked to the preceding sodiation current density (memory effect). The asymmetric behavior is also found by in situ electrochemical dilatometry. This method also shows that the effective electrode expansion during sodiation is much smaller (about +14%) compared to what is expected from Sn (+420%), which gives a reasonable explanation for the excellent cycle life for the SnNGnP (and likely other nanocomposites in general). Next to the advantages, challenges, which result from the nanocomposite approach, are also discussed.
Tin supported by nitrogen‐doped graphene nanoplatelets is found to be an efficient anode for sodium‐ion batteries. Rate‐dependent measurements and in situ diffraction reveal the asymmetric storage behavior of tin within a cycle as well as a memory effect. The in situ electrochemical dilatometry study shows the active role of the support in mitigating the large volume changes of tin during (de)sodiation.
Abstract
Lithium garnets have been widely studied as promising electrolytes that could enable the next-generation all-solid-state lithium batteries. However, upon exposure to atmospheric moisture and ...carbon dioxide, insulating lithium carbonate forms on the surface and deteriorates the interfaces within electrodes. Here, we report a scalable solid sintering method, defined by lithium donor reaction that allows for complete decarbonation of Li
6.4
La
3
Zr
1.4
Ta
0.6
O
12
(LLZTO) and yields an active LiCoO
2
layer for each garnet particle. The obtained LiCoO
2
coated garnets composite is stable against air without any Li
2
CO
3
. Once working in a solid-state lithium battery, the LiCoO
2
-LLZTO@LiCoO
2
composite cathode maintains 81% of the initial capacity after 180 cycles at 0.1 C. Eliminating CO
2
evolution above 4.0 V is confirmed experimentally after transforming Li
2
CO
3
into LiCoO
2
. These results indicate that Li
2
CO
3
is no longer an obstacle, but a trigger of the intimate solid-solid interface. This strategy has been extended to develop a series of LLZTO@active layer materials.
Plants need to cope with multitudes of stimuli throughout their lifecycles in their complex environments. Calcium acts as a ubiquitous secondary messenger in response to numerous stresses and ...developmental processes in plants. The major Ca
sensors, calcineurin B-like proteins (CBLs), interact with CBL-interacting protein kinases (CIPKs) to form a CBL-CIPK signaling network, which functions as a key component in the regulation of multiple stimuli or signals in plants. In this review, we describe the conserved structure of CBLs and CIPKs, characterize the features of classification and localization, draw conclusions about the currently known mechanisms, with a focus on novel findings in response to multiple stresses, and summarize the physiological functions of the CBL-CIPK network. Moreover, based on the gradually clarified mechanisms of the CBL-CIPK complex, we discuss the present limitations and potential prospects for future research. These aspects may provide a deeper understanding and functional characterization of the CBL-CIPK pathway and other signaling pathways under different stresses, which could promote crop yield improvement via biotechnological intervention.
A plug-and-play surface plasmon resonance (SPR) dual-parameter optical fiber biosensor is reported, in which Au film was firstly coated on the fiber surface for exciting SPR and the end half of the ...Au film was modified with Au nanoparticles to generate double SPR resonance valleys. For simultaneous detecting of glucose and cholesterol concentrations, modified P-mercaptophenylboronic acid (PMBA) and β-cyclodextrin (β-CD) were subsequently coated on the surface of sensor probe. Due to the cis-diol structure of glucose, it can interact with PMBA, leading to a red shift of one SPR resonant valley, whose maximum wavelength shift is 11.228 nm in the range of 0–1.7 mM glucose concentration. On the same time, the cholesterol molecules can realize the host-guest combination with β-CD, leading to a red shift of another SPR resonant valley, and the maximum wavelength shift is 18.893 nm in the cholesterol concentration range of 0–300 nM. The detection limits of the sensor to glucose and cholesterol are 0.00078 mM and 0.012 nM, respectively. The enhances the practical value of the dual-parameter sensor. Both theory and experiment results verify the feasibility of the “plug-and-play” sensor to measure the dual biomass of glucose and cholesterol with ultra-low detection limit and good selectivity. The proposed method provides a huge research value for the optical fiber sensor in multi-parameter measurement.
•A highly-sensitive and reflective optical fiber SPR biosensor was proposed for dual-parameter measurement.•Glucose and cholesterol concentrations could be simultaneously measured by one sensor.•Au nanoparticles were coated on the sensor to adjust the resonant wavelength and enhance the sensor sensitivity.•The cross-sensitivity between glucose and cholesterol could be neglected by selecting PMBA and β-CD as sensitive materials.•The sensor has an ultra-low detection limit and excellent selectivity for detecting low concentrations of glucose and cholesterol.
Glandular trichomes are generally considered biofactories that produce valuable chemicals. Increasing glandular trichome density is a very suitable way to improve the productivity of these valuable ...metabolites, but little is known about the regulation of glandular trichome formation. Phytohormone jasmonate (JA) promotes glandular trichome initiation in various plants, but its mechanism is also unknown.
By searching transcription factors regulated by JA in Artemisia annua, we identified a novel homeodomain-leucine zipper transcription factor, HOMEODOMAIN PROTEIN 1 (AaHD1), which positively controls both glandular and nonglandular trichome initiations. Overexpression of AaHD1 in A. annua significantly increased glandular trichome density without harming plant growth. Consequently, the artemisinin content was improved.
AaHD1 interacts with A. annua jasmonate ZIM-domain 8 (AaJAZ8), which is a repressor of JA, thereby resulting in decreased transcriptional activity. AaHD1 knockdown lines show decreased sensitivity to JA on glandular trichome initiation, which indicates that AaHD1 plays an important role in JA-mediated glandular trichome initiation.
We identified a new transcription factor that promotes A. annua glandular trichome initiation and revealed a novel molecular mechanism by which a homeodomain protein transduces JA signal to promote glandular trichome initiation. Our results also suggested a connection between glandular and nonglandular trichome formations.
Acute respiratory disease caused by 2019 novel coronavirus (2019‐nCoV) has rapidly spread throughout China. Children and adults show a different clinical course. The purpose of the current study is ...to comparatively analyze the clinical characteristics of 2019‐nCoV infection in children and adults and to explore the possible causes for the discrepancies present. The medical records of 25 adults and 7 children confirmed cases of 2019‐2019‐nCoV acute respiratory diseases were reviewed retrospectively. All children were family clusters. The total adult patients were differentiated into the local residents of Wuhan, a history of travel to Wuhan and direct contact with people from Wuhan. The numbers were 14 (56%), 10 (40%), and 1 (4%), respectively. The median incubation period of children and adults was 5 days (ranged, 3‐12 days) and 4 days (ranged, 2‐12 days), respectively. Diarrhoea and/or vomiting (57.1%) were demic by World Health Organiza more common in children, whereas for adults it was myalgia or fatigue (52%). On admission, the percentage of children having pneumonia (5%, 71.4%) was roughly the same as adults (20%, 80%). A total of 20% of adults had leucopoenia, but leukocytosis was more frequently in children (28.6%, P=.014). A higher number of children had elevated creatine kinase isoenzyme (57.1% vs 4%, P=.004). Antiviral therapy was given to all adult patients but to none of the children. In summary, knowledge of these differences between children and adults will not only be helpful for the clinical diagnosis of 2019‐nCoV disease, but also for a future discussion on age‐specific coronavirus infection.
Highlights
The routes of infection were more diverse in adults than children.
Diarrhoea and/or vomiting were more common in children, whereas for adults it was myalgia or fatigue.
More adults had leucopoenia, but leukocytosis was more frequently in children.
A higher number of children had elevated creatine kinase isoenzyme.
The percentage of children having pneumonia was roughly the same as adults.
Three nonfused ring electron acceptors (NFREAs), namely, 3TT‐C2‐F, 3TT‐C2‐Cl, and 3TT‐C2, are purposefully designed and synthesized with the concept of halogenation. The incorporation of F or/and Cl ...atoms into the molecular structure (3TT‐C2‐F and 3TT‐C2‐Cl) enhances the π–π stacking, improves electron mobility, and regulates the nanofiber morphology of blend films, thus facilitating the exciton dissociation and charge transport. In particular, blend films based on D18:3TT‐C2‐F demonstrate a high charge mobility, an extended exciton diffusion distance, and a well‐formed nanofiber network. These factors contribute to devices with a remarkable power conversion efficiency of 17.19%, surpassing that of 3TT‐C2‐Cl (16.17%) and 3TT‐C2 (15.42%). To the best of knowledge, this represents the highest efficiency achieved in NFREA‐based devices up to now. These results highlight the potential of halogenation in NFREAs as a promising approach to enhance the performance of organic solar cells.
Three nonfused ring electron acceptors (3TT‐C2‐F, 3TT‐C2‐Cl, and 3TT‐C2) are designed and synthesized with the concept of halogenation. Among them, the fluorinated acceptor 3TT‐C2‐F based devices can deliver the champion power conversion efficiency of over 17% due to enhanced the π–π stacking, improved the electron mobility, etc.
Metabolic reprogramming is a central hallmark of cancer. Therefore, targeting metabolism may provide an effective strategy for identifying promising drug targets for cancer treatment. In prostate ...cancer, cells undergo metabolic transformation from zinc‐accumulating, citrate‐producing cells to citrate‐oxidizing malignant cells with lower zinc levels and higher mitochondrial aconitase (ACO2) activity. ACO2 is a Krebs cycle enzyme that converts citrate to isocitrate and is sensitive to reactive oxygen species (ROS)‐mediated damage. In this study, we found that the expression of ACO2 is positively correlated with the malignancy of prostate cancer. Both zinc and p53 can lead to an increase in ROS. ACO2 can be a target for remodeling metabolism by sensing changes in the ROS levels of prostate cancer. Our results indicate that targeting ACO2 through zinc and p53 can change prostate cancer metabolism, and thus provides a potential new therapeutic strategy for prostate cancer.
In this study, we demonstrate that ACO2 expression positively correlates with prostate cancer malignancy and drug resistance. In addition, we found that p53 decreases SIRT3 expression and zinc increases the production of hydroxyl radicals, which lead to an increase in reactive oxygen species (ROS). Furthermore, accumulated ROS causes a decrease in ACO2 activity, which leads to mitochondrial dysfunction and results in apoptosis. Thus, ACO2 can be a target for remodeling metabolism by sensing changes in ROS of prostate cancer cells, and targeting ACO2 through zinc and p53 to change the metabolic pattern of malignant cells can provide a new therapeutic strategy for prostate cancer.
Solid‐state electrolytes (SSEs) show potential in addressing the safety issues of liquid batteries, but the poor interface contact between them and the electrodes hinders practical applications. ...Here, coordination chemistry of nitrile groups based on succinonitrile (SCN) and polyacrylonitrile (PAN) is studied on the surface of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) SSE to build the chemical bonded electrolyte/electrode interfaces. The coordination of the nitrile group and LLZTO is clarified. A deformable PAN‐modifying SCN electrolyte (PSE) interphase with stable ionic conductivity (10−4 S cm−1) and high lithium‐ion transference number (0.66) is fabricated on the surface of LLZTO electrolyte based on the coordination competition of nitrile groups. Once applied to SSBs, it endows low interface resistance and strong bonding for the electrolyte/electrode interfaces so that the initial Coulomb efficiency reaches 95.6 % and the capacity remains 99 % after 250 cycles at 25 °C.
A nitrile group‐induced coordination interphase on the surface of the LLZTO electrolyte stabilizes the electrolyte/electrode interface.
Exploiting useful contacts: The exceptional catalytic performance of a photocatalyst composed of Pd nanoparticles and mesoporous carbon nitride for the dehydrogenation of formic acid in water at room ...temperature to produce H2 gas (see picture) is due to enhanced electron enrichment of the Pd nanoparticles through charge transfer at the interface of the Mott–Schottky contact.
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