Structural characterization of polysaccharide from the peel of Trichosanthes kirilowii Maxim and its anti-hyperlipidemia activity by regulating gut microbiota and inhibiting cholesterol absorption.

The peel of Trichosanthes kirilowii Maxim, is considered one of the primary sources for Trichosanthis pericarpium in traditional Chinese medicine, exhibiting lipid-lowering properties. The impact on hyperlipidemia mice of the crude polysaccharide from the peel of T. Kirilowii (TRP) was investigated in this study. The findings revealed that TRP exhibited a significant improvement in hepatic lipid deposition. Moreover, it significantly decreased serum levels of TC, TG, and LDL-C, while concurrently increasing HDL-C. 16S rRNA amplicon sequencing technique revealed that TRP group exhibited an increased relative abundance of Actinobacteria, a down-regulated relative abundance of Ruminiclostridium, and an up-regulated relative abundance of Ileibacterium. Therefore, TRP might play a role in anti-hyperlipidemia through regulation of the intestinal milieu and enhancement of microbial equilibrium. Consequently, targeted fractionation of TRP resulted in the isolation of a homogeneous acidic polysaccharide termed TRP-1. The TRP-1 polysaccharide, with an average molecular weight of 1.00 × 104 Da, and was primarily composed of Rha, GlcA, GalA, Glc, Gal and Ara. TRP-1 possessed a backbone consisting of alternating connections between â†’ 6)-α-Galp-(1 â†’ 4)-α-Rhap-(1 â†’ 6)-α-Galp-(2 â†’ 6)-ß-Galp-(1 â†’ 6)-α-Galp-(2 â†’ 6)-ß-Galp-(1 â†’ units and branched chain containing â†’ 6)-α-Glcp-(1→, 2,4)-ß-Glcp-(1, and â†’ 4)-α-GlapA-(1→. Both TRP and TRP-1 exhibited significant disruption of cholesterol micelles, highlighting their potential as lipid-lowering agents that effectively inhibit cholesterol absorption pathways.

Quasi-Solid Sulfur Conversion for Energetic All-Solid-State Na-S Battery.

The high theoretical energy density (1274 Wh kg-1) and high safety enable the all-solid-state Na-S batteries with great promise for stationary energy storage system. However, the uncontrollable solid-liquid-solid multiphase conversion and its associated sluggish polysulfides redox kinetics pose a great challenge in tunning the sulfur speciation pathway for practical Na-S electrochemistry. Herein, we propose a new design methodology for matrix featuring separated bi-catalytic sites that control the multi-step polysulfide transformation in tandem and direct quasi-solid reversible sulfur conversion during battery cycling. It is revealed that the N, P heteroatom hotspots are more favorable for catalyzing the long-chain polysulfides reduction, while PtNi nanocrystals manipulate the direct and full Na2S4 to Na2S low-kinetic conversion during discharging. The electrodeposited Na2S on strongly coupled PtNi and N, P-codoped carbon host is extremely electroreactive and can be readily recovered back to S8 without passivation of active species during battery recharging, which delivers a true tandem electrocatalytic quasi-solid sulfur conversion mechanism. Accordingly, stable cycling of the all-solid-state soft-package Na-S pouch cells with an attractive specific capacity of 876 mAh gS -1 and a high energy of 608 Wh kgcathode -1 (172 Wh kg-1, based on the total mass of cathode and anode) at 60 °C are demonstrated.

Covalent Organic Frameworks: Their Composites and Derivatives for Rechargeable Metal-Ion Batteries.

Covalent organic frameworks (COFs) have attracted considerable interest in the field of rechargeable batteries owing to their three-dimensional (3D) varied pore sizes, inerratic porous structures, abundant redox-active sites, and customizable structure-adjustable frameworks. In the context of metal-ion batteries, these materials play a vital role in electrode materials, effectively addressing critical issues such as low ionic conductivity, limited specific capacity, and unstable structural integrity. However, the electrochemical characteristics of the developed COFs still fall short of practical battery requirements due to inherent issues such as low electronic conductivity, the tradeoff between capacity and redox potential, and unfavorable micromorphology. This review provides a comprehensive overview of the recent advancements in the application of COFs, COF-based composites, and their derivatives in rechargeable metal-ion batteries, including lithium-ion, lithium-sulfur, sodium-ion, sodium-sulfur, potassium-ion, zinc-ion, and other multivalent metal-ion batteries. The operational mechanisms of COFs, COF-based composites, and their derivatives in rechargeable batteries are elucidated, along with the strategies implemented to enhance the electrochemical properties and broaden the range of their applications.

Double design of host and guest synergistically reinforces the Na-ion storage of sulfur cathodes.

Development of room-temperature sodium-sulfur batteries is significantly hampered by the shuttle effect of soluble intermediates and intrinsically sluggish conversion kinetics. In this work, a double design host and guest strategy (i.e., implantation of a polar V2O3 adsorbent into a carbon substrate and selenium doping of a sulfur guest) is proposed to synergistically reinforce the electrochemical properties of sulfur electrodes in sodium ion storage. The V2O3 adsorbent efficiently immobilizes sulfur species via strong polar-polar interactions, while the selenium dopant improves the electronic conductivity of sulfur cathodes and accelerates the redox conversion of sulfur cathodes. The synergistic effect between the V2O3 adsorbent and selenium dopant is shown to inhibit the shuttle effect and improve the redox kinetics, thus realizing greatly enhanced Na-ion storage properties of sulfur cathodes. The as-designed sulfur cathode delivers a superior rate capability of 663 mA h g-1 at 2.0 A g-1 and demonstrates excellent cyclability of 405 mA h g-1 over 700 cycles at 1.0 A g-1.

Orthorhombic Nb2 O5 Decorated Carbon Nanoreactors Enable Bidirectionally Regulated Redox Behaviors in Room-Temperature Na-S Batteries.

Regulating redox kinetics is able to spur the great-leap-forward development of room-temperature sodium-sulfur (RT Na-S) batteries, especially on propelling their Na-ion storage capability. Here, an innovative metal oxide kinetics accelerator, orthorhombic Nb2 O5 Na-ion conductor, is proposed to functionalize porous carbon nanoreactors (CNR) for S cathodes. The Nb2 O5 is shown to chemically immobilize sodium polysulfides via strong affinity. Theoretical and experimental evidence reveals that the Nb2 O5 can bidirectionally regulate redox behaviors of S cathodes, which accelerates reduction conversions from polysulfides to sulfides as well as promotes oxidation reactions from sulfides to S. In situ and ex situ characterization techniques further verify its electrochemical lasting endurance in catalyzing S conversions. The well-designed S cathode demonstrates a high specific capacity of 1377 mA h g-1 at 0.1 A g-1 , outstanding rate capability of 405 mA h g-1 at 2 A g-1 , and stable cyclability with a capacity retention of 617 mA h g-1 over 600 cycles at 0.5 A g-1 . An ultralow capacity decay rate of 0.0193% per cycle is successfully realized, superior to those of current state-of-the-art RT Na-S batteries. This design also suits emerging Na-Se batteries, which contribute to outstanding electrochemical performance as well.

Trimodal hierarchical porous carbon nanorods enable high-performance Na-Se batteries.

Technical bottlenecks of polyselenide shuttling and material volume variation significantly hamper the development of emerging sodium-selenium (Na-Se) batteries. The nanopore structure of substrate materials is demonstrated to play a vital role in stabilizing Se cathodes and approaching superior Na-ion storage properties. Herein, an ideal nanorod-like trimodal hierarchical porous carbon (THPC) host is fabricated through a facile one-step carbonization method for advanced Na-Se batteries. The THPC possesses a trimodal nanopore structure encompassing micropores, mesopores, and macropores, and functions as a good accommodator of Se molecules, a reservoir of polyselenide intermediates, a buffer for volume expansion of Se species during sodiation, and a promoter for electron/ion transfer in the electrochemical process. As a result, Na-Se batteries assembled with the Se-THPC composite cathode realize high utilization of Se, fast redox kinetics, and excellent cyclability. Furthermore, the Na-ion storage mechanism of the well-designed Se-THPC composite is profoundly revealed by in situ visual characterization techniques.

Nanostructure Engineering Strategies of Cathode Materials for Room-Temperature Na-S Batteries.

Room-temperature sodium-sulfur (RT Na-S) batteries are considered to be a competitive electrochemical energy storage system, due to their advantages in abundant natural reserves, inexpensive materials, and superb theoretical energy density. Nevertheless, RT Na-S batteries suffer from a series of critical challenges, especially on the S cathode side, including the insulating nature of S and its discharge products, volumetric fluctuation of S species during the (de)sodiation process, shuttle effect of soluble sodium polysulfides, and sluggish conversion kinetics. Recent studies have shown that nanostructural designs of S-based materials can greatly contribute to alleviating the aforementioned issues via their unique physicochemical properties and architectural features. In this review, we review frontier advancements in nanostructure engineering strategies of S-based cathode materials for RT Na-S batteries in the past decade. Our emphasis is focused on delicate and highly efficient design strategies of material nanostructures as well as interactions of component-structure-property at a nanosize level. We also present our prospects toward further functional engineering and applications of nanostructured S-based materials in RT Na-S batteries and point out some potential developmental directions.

Metal-based electrocatalysts for room-temperature Na-S batteries.

Room-temperature sodium-sulfur (RT Na-S) batteries have recently captured intensive research attention from the community and are regarded as one of promising next-generation energy storage devices since they not only integrate the advantages in high abundance and low commercial cost of elemental Na/S but also exhibit exceptionally high theoretical capacity and energy density. Whereas, the notorious shuttle effect of soluble intermediates and sluggish kinetics remain two main obstacles for RT Na-S batteries to step into new developmental stage. Recently, impressive advancements of metal-based electrocatalysts have offered a viable solution to stabilize S cathodes and unlocked new opportunities for RT Na-S batteries. Here, we underline the recent progress on metal-based electrocatalysts for RT Na-S batteries for the first time by shedding light on this emerging but promising field. The involved metal-based electrocatalysts include metals, metal oxides, metal sulfides, metal carbides, and other metal-based catalytic species. Our emphasis is focused on the discussion of design, fabrication, and properties of these electrocatalysts as well as interactions between electrocatalysts and sodium polysulfides. Otherwise, some potential electrocatalysts for RT Na-S batteries are pointed out as well. At last, perspectives for the future development of RT Na-S batteries with S cathode electrocatalysts are offered.

An Emerging Energy Storage System: Advanced Na-Se Batteries.

Sodium-selenium (Na-Se) batteries have aroused enormous attention due to the large abundance of the element sodium as well as the high electronic conductivity and volumetric capacity of selenium. In this battery system, some primary advances in electrode materials have been achieved, mainly involving the design of Se-based cathode materials. In this Review, the electrochemical mechanism is discussed, thus revealing the main challenges in Na-Se batteries. Then, the advances in the design of Se-based cathode materials for Na-ion storage are systemically summarized, classified, and discussed, including Se/carbon composite, Se/polar material/carbon composites, and hybrid SexSy alloys. Some potential strategies enabling the improvement of crucial challenges and enhancement of electrochemical performance are also proposed to provide guidelines for the enhancements of Na-ion storage. An outlook for future valuable research directions is proposed to understand more deeply the electrochemical mechanism of Na-Se batteries and promote their further developments in full cell performance and commercialization.

Radiofrequency ablation as a treatment for hilar cholangiocarcinoma.

AIM: To explore the role of radio-frequency ablation (RFA) as a treatment for hilar cholangiocarcinoma. METHODS: Eleven patients with obstructive cholestasis underwent Computed Tomography (CT) examination, occupying lesions were observed in the hepatic hilar region in each patient. All lesions were confirmed as cholangioadenocarcinoma by biopsy and were classified as type III or IV by percutaneous transhepatic cholangiography. Patients were treated with multiple electrodes RFA combined with other adjuvant therapy. The survival rate, change of CT attenuation coefficient of the tumor and tumor size were studied in these patients after RFA. RESULTS: In a follow-up CT scan one month after RFA, a size reduction of about 30% was observed in six masses, and two masses were reduced by about 20% in size, three of the eleven masses remained unchanged. In a follow-up CT scan 6 mo after RFA, all the masses were reduced in size (overall 35%), in which the most significant size reduction was 60%. The survival follow-up among these eleven cases was 18 mo in average. Ongoing follow-up showed that the longest survival case was 30 mo and the shortest case was 10 mo. CONCLUSION: RFA is a microinvasive and effective treatment for hilar cholangiocarcinoma.