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Background: The epidemiology and risk factors for postoperative complications related to free flap reconstruction in head and neck cancer patients admitted to the Intensive Care Unit (ICU) are unknown. Methods: We performed a retrospective cohort study of patients with free flap reconstruction of head and neck cancer between September 2015 and April 2023 admitted to the ICU of Beijing Tongren Hospital. The univariate and multivariate analyses were used to explore the risk factors for postoperative complications related to free flap reconstruction admitted to ICU, including flap necrosis, bleeding, fistula, and infection. Results: A total of 239 patients were included in this study, and 38 (15.9%) patients had postoperative complications related to free flap reconstruction. The median length of ICU stay was 1 day (interquartile range, 1–2 days). Multivariate analysis found that low BMI (P < 0.001), high postoperative CRP (P = 0.005), low hemoglobin (P = 0.012), and inadequate fluid intake (P < 0.05) were independent risk factors for complications. Conclusions: Postoperative complications related to free flap reconstruction were common in this ICU population. Careful fluid management and monitoring of CRP and hemoglobin levels may reduce complications. [ABSTRACT FROM AUTHOR]

MoO 3 is a kind of promising cathode material for lithium-ion batteries (LIBs), owing to its high specific capacity (279 mA h g−1) and layered structure. However, low electrical conductivity and sluggish reaction kinetics results in poor rate and Li-ions storage capability. The introduction of oxygen vacancies (OVs) can promote Li+ diffusion, and produce great electrical conductivity. Here, we report a strategy to synergize the merits of OVs by pulsed laser deposition (PLD) by adjusting oxygen partial pressures (2～20 Pa). The appropriate OVs concentration not only significantly approves electrochemical performance but also increases pseudocapacitance contribution. The Li-ion diffusion coefficient of MoO 3−x is remarkably improved by one or two orders of magnitude compared with that of MoO 3. Therefore, this facile and efficient strategy on OVs could afford a reference for other metal oxides for high-performance electrode materials. [ABSTRACT FROM AUTHOR]

Li 3 P-VP nanocomposite has been formed by a homemade pulsed laser deposition route and its electrochemical characteristic with lithium is reported for the first time. It displays high lithium storage capability as electrode material for secondary lithium ion batteries. The Li 3 P-VP nanocomposite exhibits high specific discharge capacity of 1040.4 mAh g−1 between 0.01 and 4.0 V and the specific capacity can still maintain 95% after 50 cycles. Ex situ transmission electron microscopy reveals that VP 2 is generated from Li 3 P and VP after the first charging process to 4.0 V, while Li 3 P and V are found to be the final discharge products. In the recharging process, VP and VP 2 are formed as the delithiated products. Unlabelled Image • Li 3 P-VP nanocomposite thin film was fabricated by PLD. • High capacity of 1040.4 mAh g−1 was achieved and 95% was kept after 50 cycles. • VP 2 was generated from Li 3 P and VP after the first charging process to 4.0 V. • Reversible conversion mechanism to V and Li 3 P was suggested for VP-VP 2. [ABSTRACT FROM AUTHOR]

Abstract Polycrystalline nickel ferrite (NiFe 2 O 4) thin films were fabricated by pulsed laser deposition (PLD) and coated with nanometer layer of lithium phosphorus oxynitride (LiPON) by radio frequency magnetron sputtering (RF sputtering). Physical characterizations demonstrated that NiFe 2 O 4 thin films were not destroyed by LiPON coating with 50 nm thickness. Discharge capacity of LiPON coated NiFe 2 O 4 thin film after 50 cycles at 5 μA cm−2 was 849 mAh g−1, much higher than the counterpart value of pristine NiFe 2 O 4 thin film (449 mAh g−1), while rate capability was also greatly enhanced. Ex situ TEM investigation confirmed the two-steps reaction mechanism between NiFe 2 O 4 and Li, which includes an irreversible decomposition reaction of NiFe 2 O 4 in the first discharge process and reversible reactions between NiO, Fe 2 O 3 and their nanosized metal particles afterward. The significant improvement on the electrochemical performance was ascribed to the amorphous LiPON layer on the surface, which suppressed the volume expansion of electrode, the formation of delaminated particles and generation of cracks on electrode surface, as proved by ex situ SEM and AFM results. The LiPON coating is an effective approach to enhance the electrochemical performance of conversion materials for lithium ion batteries. Highlights • Pristine and LiPON coated NiFe 2 O 4 thin films were fabricated. • LiPON coating benefits the electrochemical performance of NiFe 2 O 4 thin film. • Conversion mechanism was confirmed by ex situ TEM technique for the first time. • Ex situ SEM and AFM results explained the effect of LiPON coating. [ABSTRACT FROM AUTHOR]

The use of coral sand in concrete and mortar for ocean engineering has led to significant reductions in construction costs and improved construction efficiency. However, this approach poses challenges such as low strength, high brittleness, and high porosity. To address these challenges, this study incorporated silica fume to enhance the mechanical properties of the mortar and investigated the effects of different silica fume contents on the hydration process, pore structure, and strength of coral sand mortar. Additionally, this study introduced a novel iterative approach combining low-field nuclear magnetic resonance and scanning electron microscopy image analysis to determine transverse relaxivity (ρ 2). During the early hydration process, the intensity spectrum of coral mortar exhibited three peaks at 298, 1841, and 299 au, corresponding to transverse relaxation times (T 2) of 0.64, 6.83, and 83.10 ms, respectively. Over a 6 h hydration period, the spectrum of the specimen prepared with white cement exhibited an additional peak that gradually merged with the main peak. As the curing period extended from 7 to 28 days, the porosity of coral sand mortar decreased by 3.77–4.55 %, while the strength increased by 7.43–14.35 MPa across silica fume contents ranging from 6 % to 24 %. With increasing silica fume content, the calcium–silicon ratio of the samples gradually decreased, promoting the formation of more floccus C–S–H gels. Consequently, the sample porosity first decreased slightly. After 28 days of curing, the coral sand mortar containing 12 % silica fume exhibited the highest strength owing to the increased amount of floccus C–S–H gels. These gels gradually filled the pores between the fibrous C–S–H gels, forming a compact spatial reticular structure. This structure mitigated the adverse impact of high porosity on mortar strength. • After 6 h of hydration, the second peak in the T 2 spectrum, attributed to the presence of white cement, disappeared. • A novel method was proposed for determining surface relaxivity (ρ 2) via LM NMR and SEM/IA. • The morphology of C–S–H gels, Ca/Si ratio, and porosity collectively influenced the compressive strength of the mortar. [ABSTRACT FROM AUTHOR]

Using first-principles calculations, we have systematically investigated the adsorption and diffusion behavior of Li in MoO 3 bulk, on MoO 3 (010) surface and in MoO 3 /graphene composite. Our results indicate that, in case of MoO 3 bulk, Li diffusion barriers in the interlayer and intralayer spaces are 0.55 eV and 0.58 eV respectively, which are too high to warrant fast Lithium-ion charge/discharge processes. While on MoO 3 (010) surface, Li exhibits a diffusion barrier as low as 0.07 eV which guarantees an extremely fast Li diffusion rate during charge/discharge cycling. However, in MoO 3 /graphene monolayer, Li diffusion barrier is at the same level as that on MoO 3 (010) surface, which also ensures a very rapid Li charge/discharge rate. The rapid Li charge/discharge rate in this system originates from the removal of the upper dangling O1 atoms which hinder the Li diffusion on the lower MoO 3 layer. Besides this, due to the interaction between Li and graphene, the Li average binding energy increases to 0.14 eV compared to its value on MoO 3 (010) surface which contributes to a higher voltage. Additionally, the increased ratio of surface area provides more space for Li storage and the capacity of MoO 3 /graphene composite increases up to 279.2 mAhg −1 . The last but not the least, due to the high conductivity of graphene, the conductivity of MoO 3 /graphene composite enhances greatly which is beneficial for electrode materials. In the light of present results, MoO 3 /graphene composite exhibits higher voltage, good conductivity, large Li capacity and very rapid Li charge/discharge rate, which prove it as a promising cathode material for high-performance lithium-ion batteries (LIBs). [ABSTRACT FROM AUTHOR]

Thermal batteries are widely used as the power sources in the field of aerospace and military applications, due to their high-power density and long storage life. Compared to the cubic transition metal disulfides, another hexagonal metal disulfide SnS 2 , is studied as a new cathode of thermal batteries. SnS 2 exhibits good environmental and thermal stability, high electronic conductivity, good wettability, as well as high discharge voltage and rate capability. Its working voltage reaches 2.23 V under discharge current of 100 mA cm−2. During the discharge process, three distinct discharge steps are existed at a cut-off voltage of 1.5 V, as described followed: 1) 2 S n S 2 + 2 L i + + 2 e − = S n 2 S 3 + L i 2 S ; 2) S n 2 S 3 + 2 L i + + 2 e − = 2 S n S + L i 2 S ; 3) SnS + 2 L i + + 2 e − = S n + L i 2 S. In conclusions, SnS 2 is proved a most promising cathode material for thermal batteries, and can be widely used. [Display omitted] • SnS 2 with good stable and wettability is used as cathode of thermal batteries. • Electrochemical behaviors of SnS 2 in molten salt are discussed and verified. • Further application of SnS 2 in thermal batteries is defined. [ABSTRACT FROM AUTHOR]

[Display omitted] • (1 1 0) orientation is favored for energy minimization of LiCoO 2 thin film. • LCO(1 1 0)/LiPON/Li shows a discharge capacity of 47 μAh cm−2 μm−1 (about 101 mAh g−1) on 10C-rate. • Oxygen reactive sputtering promotes the transformation from LiCoO 2 (1 1 0) texture to (0 0 3) texture. • LiCoO 2 (1 1 0) texture has the lowest interface and bulk resistance for Li+ transfer. The solid-solid interfaces have crucial, but still poorly understood, roles in the performance of thin-film lithium batteries (TFBs). The modulating of crystalline preferred growth orientation is an effective method to build rapid ionic diffusion channel with lower interfacial barrier. This work develops and reveals the interfacial electrochemical behaviors of textured cathode/solid electrolyte in TFBs by controlling preferred growth orientation of LiCoO 2 (LCO) thin-film. The LCO(0 0 3) texture is transformed from the (4 4 0) plane of Co 3 O 4 precursor with the lowest surface energy after annealing. Remarkably, oxygen reactive sputtering will promote the formation of LCO grains instead of Co 3 O 4 species, resulting in the growth of LCO along (1 1 0) facet with the lowest volume strain-energy after annealing. TFBs (LCO/LiPON/Li) configuration with LCO(1 1 0) texture exhibit enhanced electrochemical performance with the capacity of about 101 mAh g−1 about twice than that of (0 0 3) texture on 10C-rates, owing to the lower interface and bulk resistance. These results indicate that the method of controlling the lattice orientation not only minimize the lithium-ion diffusion pathways in the film textures, but also is beneficial to the interface between LCO and LiPON electrolyte to establish high performance solid-state batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • The research progress of NCM cathode materials is summarized. • The current problems of NCM cathode materials are systematically analyzed. • The optimization measures for NCM cathode materials are summarized. • The future development directions of NCM cathode materials are proposed. High energy–density lithium-ion batteries are in great demand in daily life, especially in the field of portable electronic equipment and electrical vehicles. Therefore, vigorous research and development of cathode materials with higher energy density to replace traditional ones is of great significance. In particular, compared with other cathode materials, layered lithium nickel cobalt manganese oxides (LiNi x Co y Mn 1-x-y O 2) have the advantages of low cost and high specific capacity. However, LiNi x Co y Mn 1-x-y O 2 still has serious problems in internal structure, safety and stability. Herein, the problems of LiNi x Co y Mn 1-x-y O 2 in the charging/discharging process and the research progress for improving their electrochemical performance through modification methods are summarized. The internal reaction mechanism of the battery and possible future development directions are also discussed. [ABSTRACT FROM AUTHOR]