Layered oxide cathodes usually exhibit high compositional diversity, thus providing controllable electrochemical performance for Na‐ion batteries. These abundant components lead to complicated ...structural chemistry, closely affecting the stacking preference, phase transition and Na+ kinetics. With this perspective, we explore the thermodynamically stable phase diagram of various P2/O3 composites based on a rational biphasic tailoring strategy. Then a specific P2/O3 composite is investigated and compared with its monophasic counterparts. A highly reversible structural evolution of P2/O3–P2/O3/P3–P2/P3–P2/Z/O3′–Z/O3′ based on the Ni2+/Ni3.5+, Fe3+/Fe4+ and Mn3.8+/Mn4+ redox couples upon sequential Na extraction/insertion is revealed. The reduced structural strain at the phase boundary alleviates the phase transition and decreases the lattice mismatch during cycling, endowing the biphasic electrode a large reversible capacity of 144 mAh g−1 with the energy density approaching 514 Wh kg−1.
A rational biphasic tailoring strategy to prepare layered composite cathodes with the desired phase ratio is proposed. Benefiting from the reversible phase transition within transition metal slabs and the decreased structure strain at the phase boundary of the intergrowth structure during Na extraction and insertion, the Com‐NaNMFT composite material demonstrates excellent electrochemical performance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Lithium-ion batteries are widely used in electric vehicles and smart grids to facilitate fast and stable energy storage at different temperatures. However, the decreased Li+ diffusion and poor ...electronic conductivity of commercial cathode materials inevitably lead to irreversible energy degradation at low temperature. Herein, we tame the relationship between diffusion and temperature of spinel LiNi0.5Mn1.5O4 cathode by incorporating Co element into transition-metal sites. The Co element into the LiNi0.5Mn1.5O4 lattice effectively improves the diffusion properties of lithium ions, enhances its electronic conductivity, and prevents the dissolution of Mn. Therefore, LiNi0.4Co0.1Mn1.5O4 could deliver a capacity retention of 93.89% at 1 C after 200 cycles at 25 °C. Even at −20 °C, it delivers 88.43% of its room-temperature capacity. Moreover, the assembled LiNi0.4Co0.1Mn1.5O4/graphite and LiNi0.4Co0.1Mn1.5O4/Li4Ti5O12 full cells both show a capacity retention of 98.03 and 86.61% at 1 C after 100 cycles, respectively. In particular, the LiNi0.4Co0.1Mn1.5O4/Li4Ti5O12 full battery still exhibits a discharge capacity of 116.9 mA h g–1 at −20 °C, reaching 90.24% of its room-temperature capacity. These results not only pave the way for improving the electrochemical performance of 5 V-based cathode materials but also provide insightful guidance for their commercial applications at low temperature.
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IJS, KILJ, NUK, PNG, UL, UM
Layered oxide cathodes usually exhibit high compositional diversity, thus providing controllable electrochemical performance for Na‐ion batteries. These abundant components lead to complicated ...structural chemistry, closely affecting the stacking preference, phase transition and Na+ kinetics. With this perspective, we explore the thermodynamically stable phase diagram of various P2/O3 composites based on a rational biphasic tailoring strategy. Then a specific P2/O3 composite is investigated and compared with its monophasic counterparts. A highly reversible structural evolution of P2/O3–P2/O3/P3–P2/P3–P2/Z/O3′–Z/O3′ based on the Ni2+/Ni3.5+, Fe3+/Fe4+ and Mn3.8+/Mn4+ redox couples upon sequential Na extraction/insertion is revealed. The reduced structural strain at the phase boundary alleviates the phase transition and decreases the lattice mismatch during cycling, endowing the biphasic electrode a large reversible capacity of 144 mAh g−1 with the energy density approaching 514 Wh kg−1.
A rational biphasic tailoring strategy to prepare layered composite cathodes with the desired phase ratio is proposed. Benefiting from the reversible phase transition within transition metal slabs and the decreased structure strain at the phase boundary of the intergrowth structure during Na extraction and insertion, the Com‐NaNMFT composite material demonstrates excellent electrochemical performance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
AIM： To investigate the anti-angiogenic and antitumor activities of recombinant vascular basement membrane-derived multifunctional peptide （rVBMDMP） in hepatocellular carcinoma （HCC）. METHODS： HepG2, ...Bel-7402, Hep-3B, HUVE-12 and L-02 cell lines were cultured in vitro and the inhibitory effect of rVBMDMP on proliferation of cells was detected by MTT assay. The in vivo antitumor efficacy of rVBMDMP on HCC was assessed by HepG2 xenografts in nude mice. Distribution of rVBMDMP, mechanism by which the growth of HepG2 xenografts is inhibited, and microvessel area were observed by proliferating cell nuclear antigen （PCNA） and CD31 immunohistochemistry. RESULTS： MTT assay showed that rVBMDMP markedly inhibited the proliferation of human HCC （HepG2, Bel-7402, Hep-3B） cells and human umbilical vein endothelial （HUVE-12） cells in a dose-dependent manner, with little effect on the growth of L-02 cells. When the ICs0 was 4.68, 7.65, 8.96, 11.65 and 64.82 μmol/L, respectively, the potency of rVBMDMP to HepG2 cells was similar to 5-fluorouracil （5-FU） with an IC50 of 4.59 μmol/L. The selective index of cytotoxicity to HepG2 cells of rVBMDMP was 13.8 （64.82/4.68）, which was higher than that of 5-FU SI was 1.9 （8.94/4.59）. The VEGF-targeted recombinant humanized monoclonal antibody bevacizumab （100 mg/L） did not affect the proliferation of HepG2, Bel-7402, Hep-3B and L-02 cells, but the growth inhibitory rate of bevacizumab （100 mg/L） to HUVE-12 cells was 87.6% ± 8.2%. AIternis diebus intraperitoneal injection of rVBMDMP suppressed the growth of HepG2 xenografts in a dose-dependent manner, rVBMDMP （1, 3, 10 mg/kg） decreased the tumor weight by 12.6%, 55.9% and 79.7%, respectively, compared with the vehicle control. Immunohistochemical staining of rVBMDMP showed that the positive area rates （2.2% ± 0.73%, 4.5%± 1.3% and 11.5% ±3.8%） in rVBMDMP treated group （1, 3, 10 mg/kg） were significantly higher than that （0.13% ± 0.04%） in the control group （P 〈 0.01）. The positive area rates （19.0% ± 5.7%, 12.2% ± 3.5% and 5.2% ±1.6% ） of PCNA in rVBMDMP treated group （1, 3, 10 mg/kg） were significantly lower than that （29.5% ± 9.4%） in the control group （P 〈 0.05）. rVBMDMP at doses of 1, 3 and 10 mg/kg significantly reduced the tumor microvessel area levels （0.26%± 0.07%, 0.12% ± 0.03% and 0.05% ± 0.01% vs 0.45% ± 0.15%） in HepG2 xenografts （P 〈 0.01）, as assessed by CD31 staining. CONCLUSION： rVBMDMP has effective and unique anti-tumor properties, and is a promising candidate for the development of anti-tumor drugs.
Carbon dots (CDs) are photoluminescent nanomaterials with wide-ranging applications. Despite their photoactivity, it remains unknown whether CDs degrade under illumination and whether such ...photodegradation poses any cytotoxic effects. Here, we show laboratory-synthesized CDs irradiated with light degrade into molecules that are toxic to both normal (HEK-293) and cancerous (HeLa and HepG2) human cells. Eight days of irradiation photolyzes 28.6-59.8% of the CDs to <3 kilo Dalton molecules, 1431 of which are detected by high-throughput, non-target high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Molecular network and community analysis further reveal 499 cytotoxicity-related molecules, 212 of which contain polyethylene glycol, glucose, or benzene-related structures. Photo-induced production of hydroxyl and alkyl radicals play important roles in CD degradation as affected by temperature, pH, light intensity and wavelength. Commercial CDs show similar photodegraded products and cytotoxicity profiles, demonstrating that photodegradation-induced cytotoxicity is likely common to CDs regardless of their chemical composition. Our results highlight the importance of light in cytocompatibility studies of CDs.
Soil salinization is a critical environmental issue restricting agricultural production. Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate ...salt stress. However, the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain inconclusive. Therefore, a four-year (2015–2018) field experiment was conducted with four levels (i.e., 0, 6, 12 and 18 Mg ha–1) of straw returned as an interlayer. Compared with no straw interlayer (CK), straw addition increased SOC concentration by 14–32 and 11–57% in the 20–40 and 40–60 cm soil layers, respectively. The increases in soil TN concentration (8–22 and 6–34% in the 20–40 and 40–60 cm soil layers, respectively) were lower than that for SOC concentration, which led to increased soil C:N ratio in the 20–60 cm soil depth. Increases in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm), which promoted uniform distributions of SOC and TN in the soil profile. Increases in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower yield. Generally, compared with other treatments, the application of 12 Mg ha–1 straw had higher SOC, TN and C:N ratio, and lower soil stratification ratio in the 2015–2017 period. The results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years, and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Ultra-thick offshore steel, known for its high strength, high toughness, and corrosion resistance, is commonly used in marine platforms and ship components. However, when offshore steel is in service ...for an extended period under conditions of high pressure, extreme cold, and high-frequency impact loads, the weld joints are prone to fatigue failure or even fractures. Addressing these issues, this study designed a narrow-gap laser wire filling welding process and successfully welded a 100-mm new type of ultra-thick offshore steel. Using finite element simulation, EBSD testing, SEM analysis, and impact experiments, this study investigates the weld's microstructure, impact toughness, and fracture mechanisms. The research found that at -80 °C, the welded joint exhibited good impact toughness (>80 J), with the impact absorption energy on the surface of the weld being 217.7 J, similar to that of the base material (225.3 J), and the fracture mechanism was primarily a ductile fracture. The impact absorption energy in the core of the weld was 103.7 J, with the fracture mechanism mainly being a brittle fracture. The EBSD results indicated that due to the influence of the welding thermal cycle and the cooling effect of the narrow-gap process, the grains gradually coarsened from the surface of the welded plate to the core of the weld, which was the main reason for the decreased impact toughness at the joint core. This study demonstrates the feasibility of using narrow-gap laser wire filling welding for 100-mm new type ultra-thick offshore steel and provides a new approach for the joining of ultra-thick steel plates.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The electrochemical behaviors of shikonin at a poly（diallyldimethylammonium chloride） functionalized graphene sheets modified glass carbon electrode（PDDA-GS/GCE） have been investigated. Shikonin ...could exhibit a pair of well-defined redox peaks at the PDDA-GS/GCE located at 0.681 V（Epa） and 0.662 V（Epc）vs. saturated calo- mel electrode（SCE） in 0.1 mol/L phosphate buffer solution（pH=2.0） with a peak-to-peak separation of about 20 mV, revealing a fast electron-transfer process. Moreover, the current response was remarkably increased at PDDA- GS/GCE compared with that at the bare GCE. The electrochemical behaviors of shikonin at the modified electrode were investigated. And the results indicate that the reaction involves the transfer of two electrons, accompanied by two protons and the electrochemical process is a diffusional-controlled electrode process. The electrochemical para- meters of shikonin at the modified electrode, the electron-transfer coefficient（a）, the electron-transfer number（n） and the electrode reaction rate constant（ks） were calculated to be as 0.53, 2.18 and 3.6 s^-1, respectively. Under the optimal conditions, the peak current of differential pulse voltammetry（DPV） increased linearly with the shikonin concentra- tion in a range from 9A72×10^-8 mol/L to 3,789×10^-6 mol/L with a detection limit of 3,157× 10^-8 mol/L. The linear regression equation was Ip=O.7366c＋0.7855（R=0.9978; lp： 10-7 A, c： 10-8 mol/L）. In addition, the modified glass carbon electrode also exhibited good stability, selectivity and acceptable reproducibility that could be used for the sensitive, simple and rapid determination of shikonin in real samples. Therefore, the present work offers a new way to broaden the analytical application of graphene in pharmaceutical analysis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In the process of developing offshore wind power towards deeper waters, the advantages of the bucket foundation in terms of integrated construction and economy are becoming increasingly evident. In ...contrast to conventional floating bodies, the air-floating bucket foundations can achieve self-floating with the help of the air in the compartment and adjust its buoyancy and stability by controlling the air volume in the compartment. The construction process of the bucket foundation involves the control of air in the compartment, thus making it more difficult to construct. Especially after the prefabrication of the bucket foundation, the stability of the bucket foundation at the floating-up stage is particularly critical. The stability of a multi-compartment bucket foundation during the floating-up process cannot be accurately evaluated as the existing theoretical method of air-floating structures does not adequately consider air compressibility. To ensure the safety of the floating-up process, a theoretical method based on the idea of intact stability has been developed to analyze the stability of the air-floating bucket foundations, which will allow accurate calculation of the righting arm for different tilt states and critical air leakage angle. At the same time, accuracy and feasibility of the proposed theoretical method are verified through indoor model tests and practical operation of the prototype structure during the floating-up process. In addition, measures to enhance the stability of the bucket foundation are proposed through sensitivity analysis of influencing factors.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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