Revealing the missing puzzle piece of concentration in regulating Zn electrodeposition.

Despite achievements in suppressing dendrites and regulating Zn crystal growth, secondary aqueous Zn batteries are still rare in the market. Existing strategies mainly focus on electrode modification and electrolyte optimization, while the essential role of ion concentration in liquid-to-solid electrodeposition is neglected for a long time. Herein, the mechanism of concentration regulation in Zn electrodeposition is investigated in depth by combining electrochemical tests, post hoc characterization, and multiscale simulations. First, initial Zn electrodeposition is thermodynamically controlled epitaxial growth, whereas with the rapid depletion of ions, the concentration overpotential transcends the thermodynamic influence to kinetic control. Then, the evolution of the morphology from 2D sheets to 1D whiskers due to the concentration change is insightfully revealed by the morphological characterization and phase-field modeling. Furthermore, the depth of discharge (DOD) results in large concentration differences at the electrode-electrolyte interface, with a mild concentration distribution at lower DOD generating (002) crystal plane 2D sheets and a heavily varied concentration distribution at higher DOD yielding arbitrarily oriented 3D blocks. As a proof of concept, relaxation is introduced into two systems to homogenize the concentration distribution, revalidating the essential role of concentration in regulating electrodeposition, and two vital factors affecting the relaxation time, i.e., current density and electrode distance, are deeply investigated, demonstrating that the relaxation time is positively related to both and is more sensitive to the electrode distance. This work contributes to reacquainting aqueous batteries undergoing phase transitions and reveals a missing piece of the puzzle in regulating Zn electrodeposition.

Asymmetric Electrode Design for High-Area Capacity and High-Energy Efficiency Hybrid Zn Batteries.

Compared to Zn-air batteries, by integrating Zn-transition metal compound reactions and oxygen redox reactions at the cell level, hybrid Zn batteries are proposed to achieve higher energy density and energy efficiency. However, attaining relatively higher energy efficiency relies on controlling the discharge capacity. At high area capacities, the proportion of the high voltage section can be neglected, resulting in a lower energy efficiency similar to that of Zn-air batteries. Here, a high-loading integrated electrode with an asymmetric structure and asymmetric wettability is fabricated, which consists of a thick nickel hydroxide (Ni(OH)2) electrode layer with vertical array channels achieving high capacity and high utilization, and a thin NiCo2O4 nanopartical-decorated N-doped graphene nanosheets (NiCo2O4/N-G) catalyst layer with superior oxygen catalytic activity. The asymmetric wettability satisfies the wettability requirements for both Zn-Ni and Zn-air reactions. The hybrid Zn battery with the integrated electrode exhibits a remarkable peak power density of 141.9 mW cm-2, superior rate performance with an energy efficiency of 71.4% even at 20 mA cm-2, and exceptional cycling stability maintaining a stable energy efficiency of ≈84% at 2 mA cm-2 over 100 cycles (400 h).

Transforming the Electrochemical Behaviors of Cobalt Oxide from "Supercapacitator" to "Battery" by Atomic-Level Structure Engineering for Inspiring the Advance of Co-Based Batteries.

Cobalt-based electrodes receive emerging attention for their high theoretical capacity and rich valence variation ability, but state-of-the-art cobalt-based electrodes present performance far below the theoretical value. Herein, the in-depth reaction mechanisms in the alkaline electrolyte are challenged and proven to be prone to the surface-redox pseudocapacitor behavior due to the low adsorption energy to OH. Using the atomic-level structure engineering strategy after substitution metal searching, the adsorption energy is effectively enhanced, and the peak of CoOOH can be observed from in situ characterization for the first time, leading to the successful transition of charge storage behavior from "supercapacitor" to "battery". When used in a Zn-Co battery as a proof of concept, it shows comprehensive electrochemical performance with a flat discharge voltage plateau of ≈1.7 V, an optimal energy density of 506 Wh kg-1 , and a capacity retention ratio of 85.1% after 2000 cycles, shining among the reported batteries. As a practical demonstration, this battery also shows excellent self-discharge performance with the capacity retention of 90% after a 10 h delay. This work subtly tunes the intrinsic electrochemical properties of the cobalt-based material through atomic-level structure engineering, opening a new opportunity for the advance of energy storage systems.

Self-Activated Formation of Hierarchical Co3 O4 Nanoflakes with High Valence-State Conversion Capability for Ultrahigh-Capacity Zn-Co Batteries.

Cobalt-based materials are attracting increasing interest in alkaline Zn batteries due to the high theoretical capacity. However, the practical utilization is restricted by the poor microstructure and insufficient valence-state conversion. Herein, a self-activated formation of hierarchical Co3 O4 nanoflakes with high valence-state conversion capability is designed. This electrode not only exhibits the optimized microstructure with large reaction surfaces, but also shows excellent valence-state conversion capability. Consequently, this battery delivers an ultrahigh capacity of 481.4 mAh g-1 and an energy density of 818.3 Wh kg-1 based on the active material, which shines among reported Co-based materials. Besides, the capacity can retain 41.9% with even 20× current density increases, and it can operate with a capacity decay of 20% after the 1000th cycle. This strategy greatly enhances the performance and durability of integrated air electrodes, raising the attention of boundary design for other electrochemical energy conversion and storage devices.

Clinical value of serum Epstein-Barr virus DNA assay in the diagnosis of nasopharyngeal carcinoma.

Serum Epstein-Barr virus DNA has been approved for diagnosing nasopharyngeal carcinoma (NPC). The goal of this meta-analysis was to evaluate the clinical value of the serum Epstein-Barr virus DNA in the diagnosis of NPC. The PubMed, Embase, Web of Knowledge, Chinese Wanfang Med Online, and National Knowledge Infrastructure (CNKI) databases were searched to identify suitable studies. The pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR) of the serum Epstein-Barr virus DNA for the diagnosis of NPC were calculated. Summary receiver operating characteristic curves were used to summarize overall test performances. Meta-Disc 1.4 and Stata 12.0 softwares were used to analyze the data. A total of 2,520 patients from ten trials were subjected to meta-analysis. The summary estimates of the serum Epstein-Barr virus DNA for NPC diagnosis were as follows: sensitivity 0.69 (95 % confidence interval (CI) 0.65-0.72), specificity 0.84 (95 % CI = 0.82-0.86), LR + 4.81 (95 % CI = 2.94-7.88), LR - 0.25 (95 % CI = 0.13-0.48), DOR 24.65 (95 % CI = 12.64-48.07), and area under the summary receiver operator characteristic (SROC) curve (AUC) was 0.8979. Our study demonstrates that the serum Epstein-Barr virus DNA could be a useful tumor marker for NPC diagnosis.

Design of Thick Electrodes with Vertical Channels for Aqueous Batteries: Experimental and Numerical Analysis.

Developing thick electrodes with high-area loadings is a direct method for boosting the energy density. However, this approach also leads to a proportional increase in the resistance to charge transport. Optimizing the microstructure of the electrode can effectively enhance the charge transport kinetics in thick electrodes. Herein, a low-tortuosity nickel electrode with vertical channels (VC-Ni) is fabricated using a phase inversion method. A high-loading VC-Ni electrode (26.7 mg cm-2) delivers a superior specific capacity of 134.0 mAh g-1 at a 5 C rate, significantly outperforming the conventional nickel electrode (Con-Ni). Numerical simulations reveal the fast transport kinetics within the vertical channel electrodes. For the thick electrode, the VC-Ni electrode shows a substantially lower concentration gradient of OH- and H+ compared to the Con-Ni electrode. Notably, beyond a critical loading of 26.5 mg cm-2, the specific capacity initially increases with volume fraction, peaking at 50%, and then diminishes. The specific capacity increases as the channel size decreases, but the tendency to increase gradually decreases. The highest specific capacity is achieved with an inverted trapezoidal channel shape, characterized by larger pores near the separator and smaller pores near the current collector. This work is of guidance for the design of thick electrodes for high-performance aqueous batteries.

[Effect and mechanism of IL-1ß/JNK transduction pathway on the nasal mucosa remodeling in allergic rhinitis rats].

OBJECTIVE: To study the role of JNK (c-Jun N-terminal kinase) signal transduction pathway on the nasal mucosa remodeling in allergic rhinitis rats, to explore whether IL-1ß participates the nasal mucosa remodeling in allergic rhinitis by JNK signal transduction pathway. METHOD: Totally 60 male Wistar rats (weighing about 200-250 g)were randomly divided into A (AR group) and B group (control group). The rats in A group were sensitized for inducing AR by intraperitoneal injection ovalbumin and Al(OH)3. Ovalbumin was respectively dropped in each nasal cavity of every rat for 4,8,12 weeks(A4,A8,or A12 group) each had 10 rats. The rats in B group were sensitized by intraperitoneal injection saline. Saline was respectively dropped in each nasal cavity of every rat for 4,8, 12 weeks(B4, B8, or B12 group), and each had 10 rats. The concentration of IL-1ß in serum and nasal lavage fluid were tested by ELASA. The protein expressions of P-JNK and P-c-Jun were detected by immunohistochemical technique. Linear correlation analysis showed the correlation between levels of IL-1ß in serum and P-JNK protein, levels of IL-1ß in nasal lavage fluid and P-JNK protein. RESULT: The concentrations of IL-1ß in serum and nasal lavage fluid of A group were all significantly higher than those of the corresponding B group (all P < 0.01). Compared with A4 group and A8 group, concentrations of IL-1ß in nasal lavage fluid of A12 group were significantly increased (all P < 0.01). However the levels of IL-1ß in serum were not significantly different among them (all P > 0.05). Mean absorbance values of P-JNK and P-c-Jun in A group were significantly higher than those in corresponding B group (all P < 0.01) and compared with A4 group and A8 group, those of A12 group were significantly increased (all P < 0.01). Strong positive correlation were found between P-JNK and concentration of IL-1ß in serum or nasal lavage fluid (r = 0.835 and r = 0.902, all P < 0.01). CONCLUSION: JNK signal transduction pathway plays important role in the nasal mucosa remodeling in allergic rhinitis rats. IL-1ß participates in AR nasal mucosa remodeling possibly partly through activating JNK signal transduction pathway.

[Role of P-JNK and P-c-Jun of JNK transduction pathway on the nasal mucosa remodeling in allergic rhinitis rats].

OBJECTIVE: To study the role of P-JNK and P-c-Jun of JNK (c-Jun N-terminal kinase) on nasal mucosa remodeling in allergic rhinitis rats. METHOD: Sixty male Wistar rats (weighing about 200-250 g) were randomly divided into AR group (A group) and B group(control group). The rats in A group were sensitized for inducing AR by intraperitoneal injection of ovalbumin and Al(OH)3. Rats in group A were randomized into A4, A8 and A12 group (each had 10 rats). Ovalbumin was dropped in each nasal cavity of every rat for 4,8,12 weeks, respectively. Rats in group B were sensitized by saline instead of OVA, and were also divided into B4, B8 and B12 group. Each group had 10 rats. Pathological changes of nasal mucosa in each period were observed by hematoxylin and eosin stain dyeing. The phosphorylation of JNK and c-Jun were tested by immunohistochemistry. RESULT: In A8 group, mucosal congestion and edema thickening with inflammatory cells infiltration of eosinophils were observed in the eighth week, and the inflammatory changes were significantly increased as time went on. The mean absorbance values of P-JNK and P-c-Jun in A group were significantly higher than those in the corresponding B group (all P < 0.01). Moreover, the mean absorbance values of A12 group were significantly higher than A4 group and A8 group (all P < 0.01 ). CONCLUSION: The expression of P-JNK and P-c-Jun in the process of nasal mucosa remodeling in allergic rhinitis rats were increased, which suggested that P-JNK and P-c-Jun played important roles in nasal mucosa remodeling of the allergic rhinitis rats.