A critical challenge in the commercialization of layer‐structured Ni‐rich materials is the fast capacity drop and voltage fading due to the interfacial instability and bulk structural degradation of ...the cathodes during battery operation. Herein, with the guidance of theoretical calculations of migration energy difference between La and Ti from the surface to the inside of LiNi0.8Co0.1Mn0.1O2, for the first time, Ti‐doped and La4NiLiO8‐coated LiNi0.8Co0.1Mn0.1O2 cathodes are rationally designed and prepared, via a simple and convenient dual‐modification strategy of synchronous synthesis and in situ modification. Impressively, the dual modified materials show remarkably improved electrochemical performance and largely suppressed voltage fading, even under exertive operational conditions at elevated temperature and under extended cutoff voltage. Further studies reveal that the nanoscale structural degradation on material surfaces and the appearance of intergranular cracks associated with the inconsistent evolution of structural degradation at the particle level can be effectively suppressed by the synergetic effect of the conductive La4NiLiO8 coating layer and the strong TiO bond. The present work demonstrates that our strategy can simultaneously address the two issues with respect to interfacial instability and bulk structural degradation, and it represents a significant progress in the development of advanced cathode materials for high‐performance lithium‐ion batteries.
Ti‐doped and La4NiLiO8‐coated Ni‐rich layered oxide cathodes are synchronously and in situ synthesized with the guidance of theoretical calculations, which exhibit good surficial stability, fast interfacial kinetic behaviors, suppressed inconsistent structural degradation in combination with markedly improved electrochemical performance. This work opens a new avenue of designing simple modification approaches and advanced cathodes for high‐energy lithium‐ion batteries.
The vesicle trafficking SYNTAXIN OF PLANTS132 (SYP132) drives hormone-regulated endocytic traffic to suppress the density and function of plasma membrane (PM) H+-ATPases. In response to bacterial ...pathogens, it also promotes secretory traffic of antimicrobial pathogenesis-related (PR) proteins. These seemingly opposite actions of SYP132 raise questions about the mechanistic connections between the two, likely independent, membrane trafficking pathways intersecting plant growth and immunity. To study SYP132 and associated trafficking of PM H+-ATPase 1 (AHA1) and PATHOGENESIS-RELATED PROTEIN1 (PR1) during pathogenesis, we used the virulent Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) bacteria for infection of Arabidopsis (Arabidopsis thaliana) plants. SYP132 overexpression suppressed bacterial infection in plants through the stomatal route. However, bacterial infection was enhanced when bacteria were infiltrated into leaf tissue to bypass stomatal defenses. Tracking time-dependent changes in native AHA1 and SYP132 abundance, cellular distribution, and function, we discovered that bacterial pathogen infection triggers AHA1 and SYP132 internalization from the plasma membrane. AHA1 bound to SYP132 through its regulatory SNARE Habc domain, and these interactions affected PM H+-ATPase traffic. Remarkably, using the Arabidopsis aha1 mutant, we discovered that AHA1 is essential for moderating SYP132 abundance and associated secretion of PR1 at the plasma membrane for pathogen defense. Thus, we show that during pathogenesis SYP132 coordinates AHA1 with opposing effects on the traffic of AHA1 and PR1.
•V-microalloying synergistically enhanced strength and toughness of HNSBS.•V addition controlled interstitial partitioning, refined coarse RA and reduced TM.•V-microalloying refined precipitates and ...restrained intergranular precipitation.•More film-like RA and dislocation martensite coordinated plastic deformation of 0.2 V steel.
High-nitrogen stainless bearing steel (HNSBS) with ultra-high tensile strength (∼ 2403 MPa) and good toughness (∼80.0 J) was obtained by V-microalloying, overcoming the strength-toughness trade-off of conventional V-free HNSBS. In this work, since V-microalloying facilitated the enrichment of interstitial atoms (C and N) in precipitates, the content of interstitial atoms in the matrix was reduced accordingly (i.e., interstitial partitioning). On the one hand, V-microalloying reduced the substantial intergranular precipitates and transformed the precipitates from M23C6 + M2N into V-containing M23C6 + M2N + MN with multi-scale particle sizes, causing a coupling strengthening effect, which contributed to the toughness and additional strength increase. On the other hand, V-microalloying controlled interstitial partitioning, effectively refined coarse retained austenite (RA), increased the fraction of dislocation martensite, and reduced the fraction of twin martensite. The more film-like RA and dislocation martensite with high dislocation density coordinated plastic deformation and prevented crack propagation, thus obviously enhancing the strength and toughness of 0.2 V steel. This study provides a new route to develop high-performance HNSBS for aerospace applications.
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Although LiNi
Co
Mn
O
is attracting increasing attention on account of its high specific capacity, the moderate cycle lifetime still hinders its large-scale commercialization applications. Herein, ...the Ti-doped LiNi
Co
Mn
O
compounds are successfully synthesized. The Li(Ni
Co
Mn
)
Ti
O
sample exhibits the best electrochemical performance. Under the voltage range of 2.7
4.3 V, it maintains a reversible capacity of 151.01 mAh·g
with the capacity retention of 83.98% after 200 cycles at 1 C. Electrochemical impedance spectroscopy (EIS) and differential capacity profiles during prolonged cycling demonstrate that the Ti doping could enhance both the abilities of electronic transition and Li ion diffusion. More importantly, Ti doping can also improve the reversibility of the H2-H3 phase transitions during charge-discharge cycles, thus improving the electrochemical performance of Ni-rich cathodes.
Precipitates always have a complex effect on the hot work hardening and recrystallization softening of materials. In this work, the dual effect of V-microalloying on hot deformation behavior and ...microstructure evolution of high nitrogen martensitic stainless steel (HNMSS) was investigated by hot compression experiments, modeling study and microstructure characterization. The results showed that V-microalloying enhanced the flow stresses and activation energy of 0.2V steel due to the fine grain strengthening effect and the blocking effect of dynamic precipitation on dislocation movement and grain boundary migration. On the other hand, the recrystallization model and deformed microstructure indicated the more intense dynamic recrystallization (DRX) softening effect in 0.2V steel, inducing the faster decrease of flow stress after the peak stress. V-microalloying promoted the dynamic precipitation of HNMSS during hot deformation, which reduced the size and increased the number of precipitates in 0.2V steel. The fine precipitates hindered dislocation movement, promoted dislocation accumulation and entanglement, formed a particle deformation zone (PDZ) with high dislocation density and large orientation gradient, and then induced the occurrence of particle-stimulated nucleation (PSN). In addition, the dislocation cells evolved from dislocation entanglement were also favorable nucleation sites for DRX.
Prediction of post-stroke functional outcome is important for personalized rehabilitation treatment, we aimed to develop an effective nomogram for predicting long-term unfavorable functional outcomes ...in ischemic stroke patients after acute phase.
We retrospectively analyzed clinical data, rehabilitation data, and longitudinal follow-up data from ischemic stroke patients who underwent early rehabilitation at multiple centers in China. An unfavorable functional outcome was defined as a modified Rankin Scale (mRS) score of 3-6 at 90 days after onset. Patients were randomly allocated to either a training or test cohort in a ratio of 4:1. Univariate and multivariate logistic regression analyses were used to identify the predictors for the development of a predictive nomogram. The area under the receiver operating characteristic curve (AUC) was used to evaluate predictive ability in both the training and test cohorts.
A total of 856 patients (training cohort:
= 684; test cohort:
= 172) were included in this study. Among them, 518 patients experienced unfavorable outcomes 90 days after ischemic stroke. Trial of ORG 10172 in Acute Stroke Treatment classification (
= 0.024), antihypertensive agents use odds ratio (OR) = 1.86;
= 0.041, 15-day Barthel Index score (OR = 0.930;
< 0.001) and 15-day mRS score (OR = 13.494;
< 0.001) were selected as predictors for the unfavorable outcome nomogram. The nomogram model showed good predictive performance in both the training (AUC = 0.950) and test cohorts (AUC = 0.942).
The constructed nomogram model could be a practical tool for predicting unfavorable functional outcomes in ischemic stroke patients underwent early rehabilitation after acute phase.
The high voltage application of the LiNi0.5Co0.2Mn0.3O2 cathode is still hindered by its unstable surficial structure and poor capacity retention. Surface coating has been proved to be an effective ...strategy to deal with these problems. However, previous multistep surface coating approaches greatly complicate the synthesis procedure. In this work, a simple and large-scale solid-state approach is developed to prepare lanthanum-based oxides co-coated LiNi0.5Co0.2Mn0.3O2 cathode materials. Electrochemical tests indicate that the co-coated samples exhibit superior cycle life and higher rate performance than those of the pristine sample. Further studies reveal that the enhanced interface stability and facilitated electron transportation can be attributed to the synergetic contribution provided by the lanthanum-based oxides co-coating layer. The present work demonstrates that our approach can achieve cathode synthesis and surface coating synchronously, and shows great potential to apply on a large scale and extent to all Ni-rich cathodes.
•Lanthanum-based oxide co-coated LiNi0.5Co0.2Mn0.3O2 is prepared via a simple route.•The smart route achieves cathode synthesis and surface coating simultaneously.•The co-coated LiNi0.5Co0.2Mn0.3O2 shows superior electrochemical performance.•The co-coating layers enhance the de-lithiation kinetic and conductivity.•The co-coating layers suppress electrochemical degradation.
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•Fluorophotometry has great advantages in sensing low concentration of ferric ions.•Visual detection platform is achieved via a portable colorimeter or smartphone.•The optical and ...visual multi-mode Fe3+ probes perform well in real water samples.
Abnormal iron ions levels may lead to some diseases and serious environmental pollution. Herein, optical and visual detection strategies of Fe3+ in water based on co-doped carbon dots (CDs) were established in the present study. Firstly, a one-pot synthetic strategy for the preparation of the N, S, B co-doped CDs with a home microwave oven was developed. Secondly, the optical properties, chemical structures, and morphology of CDs were further characterized by fluorescence spectroscopy, Uv–vis absorption spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscope. Finally, the results indicated that the fluorescence of the co-doped CDs was quenched by ferric ions via the static mechanism and the aggregation of CDs, accompanied by the increased red color. The multi-mode sensing strategies of Fe3+ with fluorescence photometer, UV–visible spectrophotometer, portable colorimeter and smartphone had the advantages of good selectivity, excellent stability and high sensitivity. Fluorophotometry based on co-doped CDs was a powerful probe platform for measuring lower concentrations of Fe3+ due to its higher sensitivity, better linear relationship, lower limit of detection (0.27 μM) and limit of quantitation (0.91 μM). In addition, the visual detection methods with a portable colorimeter and smartphone had been proven to be very suitable for rapid and simple sensing of higher concentrations of Fe3+. Moreover, the co-doped CDs utilized for Fe3+ probes in tap water and boiler water obtained satisfactory results. Consequently, the efficient, versatile optical and visual multi-mode sensing platform could be extended to apply such a visual analysis of ferric ions in the biological, chemical and other fields.
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