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Among the various anodes, Li3VO4 is a potential intercalation kind anode used in lithium-ion batteries (LIBs) that exhibits safer discharge voltage and higher capacity than graphite, a lower voltage plateau than Li4Ti5O12, and smaller volume difference in the Li+ intercalation/deintercalation process than metals and alloys. However, the comparatively low electronic conductivity, low initial coulombic efficiency (ICE) and serious capacity decay make the Li3VO4 anode unviable when it comes to practical implementation. Therefore, this paper reviews the research progress of Li3VO4 in recent years, mainly including the strategies of developing different synthesis methods to construct unique morphology, through coating, compositing or elemental doping to increase the ICE, electronic conductivity and the cycle constancy. Moreover, the application of Li3VO4 anode materials in other energy storage systems is summarized. Lastly, the development prospect and challenge of Li3VO4 anodes are discussed.

The hydrogen-based clean energy infrastructure provides a viable option for resilience improvement against extreme events, e.g., natural disaster and malicious attacks. This paper presents a resilience-oriented operation model for industrial parks energized by integrated hydrogen-electricity-heat microgrids, which aims to improve the load survivability under contingency status. The synergies of multi-type distributed energy resources (e.g., fuel cells, hydrogen storage tanks, battery storage and heat storage unit) and the sequential operation of the industrial distribution network are analytically represented by a mixed-integer second-order conic program (SOCP) formulation. Moreover, by leveraging the information of probabilistic disaster prediction, a risk-averse receding horizon method is developed to handle the uncertainty of network contingencies, and supports the optimal decision of proactive and emergency scheduling. Numerical results on a 26-node industrial energy system demonstrate the effectiveness of the proposed model and resilient scheduling method. The synergetic operation of hydrogen-based microgrids could significantly reduce the risks of load interruption.

The oxidation behavior of melt-infiltrated SiC–TiB2 ceramic composites at 500–1300 °C in air for 32 h was investigated by the isothermal oxidation test. The phase composition and microstructure evolution were studied through examining the surficial and cross-sectional oxide layer by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The oxidized surfaces were covered by scattered TiO2 particles, a continuous B2O3 layer, a B2O3–Al2O3 layer or a mullite layer depending on the oxidation temperature. The thickness of the oxide layer increased from 10 to 30 μm as the oxidation temperature increased from 900 to 1300 °C. The analysis of the weight gain data revealed that the parabolic rate constant of melt-infiltrated SiC–TiB2 ceramic composites generally increased from 4.05 × 10−3 to 3.16 × 10−1 mg2/cm4/s, accompanied with a changed oxidation nature from parabolic to cubic, as oxidation temperature increased from 500 to 1300 °C. Formation of continuous B2O3 or Al2O3-based (Al2O3–B2O3 or Al2O3–SiO2) layer were identified on the surface of SiC–TiB2 ceramic composites after being oxidized at 700–1300 °C, which was responsible for the excellent oxidation resistance of such composites. The oxidation rate of the melt-infiltrated SiC–TiB2 ceramic composites was controlled by reaction rate of the composites at 500 °C and diffusion rate of oxygen through continuous B2O3 or Al2O3-based layer to the unaffected composites at 700–1300 °C.

The strategy of “template sacrifice method” was proposed to synthesize well-defined NiSb/CoSb nanoparticles embedded in carbon nanosphere (Ni-Co-Sb/C, ~560 nm) by calcination treatment of the Ni-Co-MOF (metal-organic framework) precursor. Due to the structural controllability of MOF precursor and Ni/Co bimetallic synergy, the fabricated Ni-Co-Sb/C demonstrates a high surface area (88 m2 g−1) and superior ion conductivity, thus an excellent electrochemical performance as has been achieved as lithium ion battery (LIB) anode. A reversible discharge specific capacity as high as 495.1 mAh g−1 has been stably delivered after 1000 cycles at a high current density of 1.0 A g−1. In addition, the charge transfer impedance of Ni-Co-Sb/C electrode is as low as 67.6 Ω in the 30th cycle at 0.1 A g−1 and the pseudocapacitive contribution is as high as 73.8% at 0.5 mV s−1. The alloying mechanism of Ni-Co-Sb/C has been verified by in-situ X-ray diffraction (XRD), which enables a high lithium storage capacity. Moreover, the full-cell assembled with LiCoO2 as cathode exhibits a steady discharge specific capacity of 354.0 mAh g−1 at 0.1 A g−1 even after 100 cycles. Our work provides an effective method for the application and high-capacity Sb-based material in energy storage fields, and this material is expected as a promising candidate for a novel anode material in LIBs.

Ameliorating the interfacial issues of the zinc anode, particularly dendrite growth and electrode corrosion, is imperative for rechargeable zinc metal batteries. Herein, an electrochemical-inert li...

Irrational application of chemical fertilizers causes soil nutrient imbalance, reduced microbial diversity, soil diseases, and other soil quality problems and is one of the main sources of non-point pollution. The application of microbial inoculant (MI) can improve the soil environment and crop growth to reduce problems caused by irrational application of chemical fertilizers. Field experiments were carried out in high-phosphorus soils to study the effects of the addition of various MIs combined with chemical fertilizers on soil properties, wheat growth, and soil microbial composition and structure. The MIs consisted of one fungal agent: Trichoderma compound agent (TC) and five bacterial agents, namely soil remediation agent (SR), anti-repeat microbial agent (AM), microbial agent (MA), plant growth-promoting rhizobacteria (PG), and biological fertilizer agent (BF). The wheat yield increased by 15.2–33.4% with the addition of MIs, and PG with Bacillus subtilis as the core microorganism had the most obvious effect on increasing the production (p

A series of novel N-doped carbon-coated Li3V2(PO4)3 (LVPC/N) composites were synthesized by rheological phase method with melamine as nitrogen source. The results showed that N-doping did not affect the main structure of Li3V2(PO4)3/C (LVPC) but only changed the structure and properties of the coating layer, which effectively improved the structural stability and electrochemical performance of LVPC. When the ratio of citric acid to melamine was 5:3, the properties of LVPCN composite were the best. The initial discharge specific capacity was 195 mAh g−1 at 30 mA g−1 in the voltage range of 3.0–4.8 V. After 100 cycles of charge and discharge, the discharge capacity was still 165 mAh g−1, and the capacity retention rate was increased to 85%. Owing to the low cost, high initial discharge capacity, and long lifespan, we believe that the LVPC/N composite is significantly competitive to other cathode materials for application in lithium-ion batteries.

Due to its high theoretical capacity (∼280 mA h g−1), lithium vanadium oxide (LiV3O8) is considered a promising electrode material for meeting the demands for a longer battery life. However, it still suffers from an inferior cycling stability and rate properties. Benefitting from the unique traits of rare earth metal La, La-doping was introduced to V-sites, leading to an expansion of the lattice volume and reduced particle size, and bringing about more oxygen defects for fast ion redox reactions. The considerable discharge capacity of optimized La-doped LiV3O8 could reach up to 308 mA h g−1, and the capacity could be kept at 252 mA h g−1 after numerous loops. Supported by a detailed analysis of the capacity curves, an improved redox activity of V5+ was strongly demonstrated. Moreover, compared to the basic materials, an increasing rate capacity located in the low potential range was detected, ascribed to the existence of an oxygen vacancy, enabling a reduction in the energy barrier and a broadening of the energy distribution. Interestingly, La-doping could ultimately improve the capacity and is thus worth further exploration, particularly for the design of advanced cathodic materials.

The low electronic conductivity of spinel-structured Li4Ti5O12 could be improved by introducing CuV2O6. Herein, several Li4Ti5O12/CuV2O6 composites with different CuV2O6 contents have been successfully prepared by a facile liquid-phase dispersion technique. The amount of CuV2O6 in composites is shown to affect the particle size and electrochemical performances of Li4Ti5O12. The Li4Ti5O12/CuV2O6 composite prepared with a 5 wt % CuV2O6 content (referred to as 5 wt % Li4Ti5O12/CuV2O6) exhibits the best electrochemical performances among all the Li4Ti5O12/CuV2O6 composites. The initial discharge/charge capacities of the 5 wt % Li4Ti5O12/CuV2O6 composite reach 241.1/199.8 mAh g-1 and retain at 136.8/135.7 mAh g-1 over 500 cycles at 30 mA g-1 between 1.0 and 3.0 V. In addition, initial discharge/charge capacities of the 5 wt % Li4Ti5O12/CuV2O6 composite amount to 129.8/90.5 mAh g-1 even at 1200 mA g-1 with maintained discharge/charge capacities of 71.1/71.1 mAh g-1 over 2500 cycles, which are superior to the pristine Li4Ti5O12 in all cases. The detailed electrode kinetic analysis reveals that the introduction of the CuV2O6 phase can enhance the lithium-ion transferring rate and cycling stability of Li4Ti5O12. The enhanced lithium-storage mechanism of the 5 wt % Li4Ti5O12/CuV2O6 composite is clarified by in situ X-ray diffraction (XRD) analysis. The acquired data confirms that in situ formation of small amounts of metallic Cu during discharge/charge processes highly enhance the electronic conductivity and decreases the charge-transfer resistance of Li4Ti5O12. In sum, the as-obtained 5 wt % Li4Ti5O12/CuV2O6 composite has potential for future construction of high-rate and long-lifespan anode materials for Li-ion batteries. The work also provides an innovative route to improve electrochemical performances of Li4Ti5O12.

Environmental pollution and energy shortage make the development of clean energy more and more urgent. As a kind of clean renewable energy, hydrogen have attracted great attentions in recent years. Recently, Co3O4-based materials have emerged as promising candidates for electrocatalytic hydrogen evolution reaction (HER), due to their attractive electrocatalytic activity, low cost as well as the electrochemical durability, which make it attract widely attentions. In this review, we summarize the application of Co3O4-based materials in electrocatalytic HER, including pure Co3O4, the doped Co3O4 and the Co3O4-based composite materials. Furthermore, the strategies to enhance their electrocatalytic performance are summarized and discussed, such as morphological engineering, doping, as well as compositing with other materials. Finally, the limitation and challenges of Co3O4-based materials for HER, as well as their prospects for future research, are proposed. We believe that this review will be helpful for scientists to seek promising HER electrocatalytic materials.

As new-generation electrochemical energy-storage systems, lithium-ion capacitors (LICs) have combined the advantages of both lithium-ion batteries and supercapacitors, manifesting the merits of high-energy density under power density. Triggered by outstanding physicochemical characteristics and two different charge-storage mechanisms (including the Li+ insertion and electric double-layer capacitor characteristics), carbon materials have been intensively studied for fabricating high-performance LICs. However, the construction of high-performance LICs have been greatly limited by the unbalanced capacity and kinetic imbalance between the sluggish ion diffusion process of anode and fast electrostatic accumulation behavior of cathode. Thus, aimed at improving two different electrochemical storage performances, rational design of carbon materials has been summarized in this short review, which provide the directional guidance for engineering optimized carbon electrodes and become a breakthrough for improving energy/power densities of LICs. Furthermore, the prospects and unresolved scientific issues of LICs are also proposed.

The design and development of low-cost sorbents is vital for CO2 capture from flue gases. In this study, the lignite char from Ordos coal (SE) was treated by a one-step KOH activation method to prepare microporous activated carbons for CO2 adsorption. The textural pore properties, surface functional groups and element contents of SE before and after activation were characterized and discussed; the effects of the mass ratio of KOH to SE, activation temperature and time, as well as the adsorption temperature on CO2 adsorption for prepared porous sorbents were investigated and optimized; the isosteric heat of adsorption and adsorption kinetics for the optimized sorbent were further calculated and fitted. When the mass ratio of KOH to SE was 1 : 1, the activation temperature and time were 700 °C and 120 min respectively, and the sorbent of K/SE700(120) showed an adsorption capacity of 1.35 mmol g−1 at 20 °C, which dropped by 2.96% after ten regenerations. The Langmuir adsorption isotherms fitted the adsorption data of K/SE700(120) well, and the isosteric heats of adsorption were 11–13 kJ mol−1, showing the physisorption characteristic. In addition, the good fit of the adsorption data to the Avrami model suggested that there are multiple adsorption routes for K/SE700(120).

In search for novel cathode materials for lithium, sodium, and potassium ion batteries, organic electrode materials are expected to be the next powerful candidates owing to their high theoretical c...

In this study, NaV3O8 nanorods are successfully prepared using nonionic surface-active agents Pluronic-F127 as structure-directing agent. The as-prepared NaV3O8 nanorods calcinated at different temperatures are characterized by various techniques, including X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy. The NaV3O8 calcinated at 400 °C for 20 h shows appropriate sizes and uniform morphologies of the nanorods, 4–7 μm in length and 0.2–0.5 μm in diameter. The NaV3O8 nanorods as cathode materials for Na-ion batteries deliver high discharge capacity reaching up 110.4 mAh g−1 at current density of 120 mA g−1, as well as long lifespan by maintaining capacity of 162.1 mAh g−1 after 500 charge-discharge cycles. Also, a high reversible capacity of 83.9 mAh g−1 can be retained after 500 cycles at high rate of 2 A g−1. The obtained outstanding electrochemical performances are associated with the unique micro-nano structures, which does not only facilitate transport of Na+ ion, but also resist erosion from electrolytes. Overall, the results suggest the promise of NaV3O8 nanorods as cathode materials for high capacity, high power and long lifespan Na-ion batteries. This work may open an innovative route to discover diverse electrode materials with nanostructure for energy storage system.

A series of LiNi1/3Co1/3Mn1/3O2/polytriphenylamine composites were successfully synthesized by ultrasound dispersion method. LiNi1/3Co1/3Mn1/3O2/polytriphenylamine (5.0 wt%) composite with small and homogeneous particle size exhibited excellent electrochemical performance, which delivered an initial discharge capacity of 223.7 mAh g−1 with a capacity retention of 84.39% after 100 cycles in the voltage range of 2.5–4.5 V and at a current density of 0.2C. Moreover, an excellent specific discharge capacity of 127.3 mAh g−1 at a current density 5C indicates a superior rate performance of the LiNi1/3Co1/3Mn1/3O2/polytriphenylamine (5.0 wt%) composite. The good electrochemical performances of the composite can be attributed to the introduction of polytriphenylamine, which increased electrical conductivity, decreased charge transfer resistance and increased Li+ ion diffusion ability. These noteworthy results demonstrated that LiNi1/3Co1/3Mn1/3O2/polytriphenylamine composites might be potential cathode materials for lithium ion batteries.

Because of sodium abundance, sodium ion batteries attract a lot of attention for advanced energy storage applications. As the main member of cathodes, NASICON-type structured Na3V2(PO4)3 contributes excellent ion shuttling rate and structure stability. However, the low electrical conductivity (

In this study, in order to improve the tensile strength and toughness of dense C/SiC-SiBC, the thickness of PyC interphase (ePyC) was increased from 200 nm to 400 nm. C/SiC (ePyC≈200 nm) was also fabricated as a benchmark comparison. C/SiC-SiBC (ePyC≈200 nm) exhibited higher axial thermal residual stress (TRS) than C/SiC (ePyC≈200 nm). Increased axial TRS resulted in increased interfacial shear strength (τ) through fiber bending, which caused lowered mechanical properties of C/SiC-SiBC (ePyC≈200 nm). By increasing the thickness of PyC interphase from 200 nm to 400 nm, the axial TRS in C/SiC-SiBC decreased. Accordingly, the radial stress induced by fiber bending decreased, leading to a reduced τ in C/SiC-SiBC (ePyC≈400 nm). Decreased axial TRS and τ are beneficial to the effective loading of fiber bundles and pull out of fibers. Therefore, C/SiC-SiBC (ePyC≈400 nm) performed excellent tensile strength (250 ± 11 MPa) and fracture toughness (23.7 ± 0.5 MPa·m1/2).

ZnSe is regarded as a promising anode material for reversible Li-ion batteries because of its high theoretical capacity. Herein, we report a facile chemical precipitation method to controllably synthesize ZIF-8 nanocubes and then select them as sacrificial templates to prepare ZnSe nanoparticles embedded N-doped carbon nanocubes. The as-obtained ZnSe/carbon nanocomposite at 600 °C demonstrates a high initial discharge capacity of 1170.8 mAh g−1 with the initial columbic efficiency of 68.8% at the current density of 0.1 A g−1 in the voltage range of 0.01–3 V. In addition, it displays a reversible capacity of 1166.6 mAh g−1 after 500 cycles at the current density of 0.5 A g−1, indicating the excellent cyclic stability for the designed composites. The enhanced electrochemical performance can be ascribed to its high specific surface area (493.45 m2 g−1) and unique mesoporous structure, which provides efficient Li+ transport channels and additional storage sites. Furthermore, the existence of faradaic pseudocapacitance in ZnSe/carbon nanocomposites also affords additional capacity and contributes to the increased capacity with respect to charge/discharge cycle number.

Co nanoparticles embedded in nitrogen-doped carbon nanocubes (Co/NCs) for applications as anode materials in rechargeable lithium-ion batteries were synthesized by calcining Co-based metal-organic framework. Sizes of Co nanoparticles were ∼15 nm according to X-ray diffraction (XRD) and transmission electron microscopy. Electrochemical performances of the as-prepared anode nanocube composite at 700 °C showed a high initial capacity of 1375.1 mAh g-1 in the voltage range of 0.01-3.0 V at the current rate of 0.1 A g-1. After 100 cycles, capacity remained at 688.6 mAh g-1. Thereinto, the role of Co nanoparticles in electrochemical reaction was also elucidated by in situ XRD experiment. Capacity increase of Co/NCs at the high currents was observed, which are potentially caused by the activation of electrode and pseudocapacitance during cycling. High surface area and abundant mesopores contributed to the improved electrochemical performances of the anode, providing numerous pathways and sites for Li+ transfer and storage and accordingly contributing to pseudocapacitance capacity.

The excellent energy storage performance of covalent sulfur-carbon material has gradually attracted great interest. However, in the electrochemical sodium storage process, the bond evolution mechanism remains an elusive topic. Herein, we develop a one-step annealing strategy to achieve a high covalent sulfur-carbon bridged hybrid (HCSC) utilizing phenylphosphinic acid as the carbon-source/catalyst and sodium sulfate as the sulfur-precursor/salt template, in which the sulfur mainly exists in the forms of C–S–C and C–S–S–C. Notably, most of the bridge bonds are electrochemically cleaved when the cycling voltage is lower than 0.6 V versus Na/Na+, leading to the appearance of two visible redox peaks in the following cyclic voltammogram (CV) tests. The in-situ and ex-situ characterizations demonstrate that S2− is formed in the reduction process and the carbon skeleton is concomitantly and irreversibly isomerized. Thus, the cleaved sulfur and isomerized carbon could jointly contribute to the sodium storage in 0.01–3.0 V. In a Na-S battery system, the activated HCSC in cut off voltage window of 0.6–2.8 V achieves a high reversible capacity (770 mA h g−1 at 300 mA g−1). This insight reveals the charge storage mechanism of sulfur-carbon bridged hybrid and provides an improved enlightenment on the interfacial chemistry of electrode materials.

As an anode for lithium-ion batteries, metallic bismuth (Bi) can provide a superb volumetric capacity of 3800 mA h cm–3, showing perspective value for application. It is a pity that the severe volu...

A simple and efficient synthetic route was developed to obtain composites by mechanically ball-milling Li2ZrO3 (LZO) with Li3V2(PO4)3/C (LVPC). LZO improves the ionic conductivity of LVPC, compensates for the transfer of Li+ between the LVPC and the electrolyte, reduces the impedance of LVPC, and protects LVPC from side reactions caused by direct contact with the electrolyte. The composite consisting of 4.0 wt% of LZO exhibited a considerable electrochemical performance. The 1st discharge capacity reached 192 mAh g−1 at 30 mA g−1 between 3.0 and 4.8 V, and remained at 153 mAh g−1 after 50 cycles. The EIS analysis showed that the charge transfer and diffusion of Li+ in the LZO-LVPC composites were more favorable than those of pristine LVPC. The synthetic method proposed in this work is simple and efficient, which is convenient for large-scale production.

Triacylglycerol Lipases (TGLs) are the major enzymes involved in triacylglycerol catabolism. TGLs hydrolyze long-chain fatty acid triglycerides, which are involved in plant development and abiotic stress responses. Whereas most studies of TGLs have focused on seed oil metabolism and biofuel in plants, limited information is available regarding the genome-wide identification and characterization of the TGL gene family in tomato (Solanum lycopersicum L.). Based on the latest published tomato genome annotation ITAG4.0, 129 SlTGL genes were identified and classified into 5 categories according to their structural characteristics. Most SlTGL genes were distributed on 3 of 12 chromosomes. Segment duplication appeared to be the driving force underlying expansion of the TGL gene family in tomato. The promoter analysis revealed that the promoters of SlTGLs contained many stress responsiveness cis-elements, such as ARE, LTR, MBS, WRE3, and WUN-motifs. Expression of the majority of SlTGL genes was suppressed following exposure to chilling and heat, while it was induced under drought stress, such as SlTGLa9, SlTGLa6, SlTGLa25, SlTGLa26, and SlTGLa13. These results provide valuable insights into the roles of the SlTGL genes family and lay a foundation for further functional studies on the linkage between triacylglycerol catabolism and abiotic stress responses in tomato.

Supramolecular eutectogels, an emerging class of materials that have just developed very recently, offer a new opportunity for generating functional supramolecular gel materials in biocompatible anhydrous or low-water media. As the first example of supramolecular G4 eutectogels, complexes of natural guanosine and H3 BO3 exhibited excellent gelation capacity in choline chloride/alcohol deep eutectic solvents. The as-prepared supramolecular eutectogels displayed unexpected solvent-induced chiral inversion and significantly high ionic conductivity (up to 7.78 mS cm-1 ), as well as outstanding thixotropic/injectable properties, high thermal stability and excellent electrochromic activity. These features make these versatile supramolecular G4 eutectogels promising candidates for developing next-generation flexible electronics with low environmental impact.

Compared with other materials, monoclinic Li1+xV3O8 as the promising cathode includes many strong points, such as high theoretical capacity, abundant raw materials, safety characteristic and low environmental impact. However, the primary problems facing the development of Li1+xV3O8 for energy storage devices are poor cycling performance, low rate capability and short service life. Recently, many researches have taken various measures to overcome these shortcomings. In this mini-review, we summarized the recent developments of Li1+xV3O8 and focus on the improving of Li1+xV3O8 by ions-doping, which is deemed to a significant manner to improve the electrochemical performances of Li1+xV3O8.

To reduce the cost of CO2 capture, polyethylene polyamine (PEPA), with a high amino density and relatively low price, was loaded into MCM-41 to prepare solid sorbents for CO2 capture from flue gases. In addition, methoxypolyethylene glycol (MPEG) was codispersed and coimpregnated with PEPA to prepare composite sorbents. The pore structures, surface functional groups, adsorption and regeneration properties for the sorbents were measured and characterized. When CO2 concentration is 15%, for 30, 40 and 50 wt% PEPA-loaded MCM-41, the equilibrium adsorption capacities were respectively determined to be 1.15, 1.47 and 1.66 mmol g−1 at 60 °C; for 30 wt% PEPA and 20 wt% MPEG, 40 wt% PEPA and 10 wt% MPEG, and 50 wt% PEPA and 5 wt% MPEG codispersed MCM-41, the equilibrium adsorption capacities were respectively determined to be 1.97, 2.22 and 2.25 mmol g−1 at 60 °C; the breakthrough and equilibrium adsorption capacities for 50 wt% PEPA and 5 wt% MPEG codispersed MCM-41 respectively reached 2.01 and 2.39 mmol g−1 at 50 °C, all values showed a significant increase compared to PEPA-modified MCM-41. After 10 regenerations, the equilibrium adsorption capacity for codispersed MCM-41 was reduced by 5.0%, with the regeneration performance being better than that of PEPA-loaded MCM-41, which was reduced by 7.8%. The CO2-TPD results indicated that the mutual interactions between PEPA and MPEG might change basic sites in MCM-41, thereby facilitating active site exposure and CO2 adsorption.

Osmotic adjustments play a fundamental role in plant responses to water deficit. For apple (Malus domestica) trees growing in the primary production areas of China, drought and low phosphorus (P) levels are the main sources of abiotic stress. Although tolerance to drought and low P are important breeding goals for cultivar improvement, there is little information on natural variation within Malus for these traits or the molecular mechanisms that may mediate tolerance. In this study, it was found that in plants grown under conditions of osmotic and low P stress, electrolyte leakage and photosynthetic parameters were significantly higher, but chlorophyll concentrations were lower compared with nonstressed plants. These physiological indicators revealed that, under low P condition, the order of osmotic stress resistance (high to low) was Malus sieversii (Ms) → Malus prunifolia (Mp) → Malus hupehensis (Mh). Expression of the phosphorus transporter genes PHT1;7, PHT1;12, and PHT2;1 in the roots and PHT1;12 and PHT4;5 in the leaves was positively correlated with plant osmotic resistance. It is proposed that the highly expressed PHT genes might improve P absorption and transport efficiency, resulting in the high osmotic stress resistance under low P level conditions in Malus species.

The type and fineness of soil are commonly recognized as the two major factors affecting the frost heave behavior of foundation. This paper aims to study the effect of soil type and fineness on frost heave behavior by experimental and numerical methods. Optical and scanning electron microscopes were employed to study the microstructure of kaolin and montmorillonite soils. A finite volume method, considering the changes of thermal and water fields simultaneously, was used to model the frost heave behavior of finely grained soil. By coupling the rigid ice model with the modified Kozeny–Carman equation and estimating the hydraulic conductivity, the relationship between the frost heave ratio and specific surface area of fines was established. Based on the modeling results, a region of proportion range of three typical soil (silty, clay and sandy soil) was proposed based on the ternary plot of frost heave values. Microscopic test results show that the multilayer microstructure of kaolin results in high content of bonded water compared with that of montmorillonite, leading to higher frost heave value. This model is proved to be reliable by a good agreement between the predicted and measured frost heave values.

Although LiV3O8 is regarded as a potential cathode candidate for rechargeable lithium batteries, it has been restricted by its weak dissolution and lattice structure change. Here, polydiphenylamine is successfully introduced to trigger the evolution of LiV3O8 material through an in situ oxidative polymerization method, significantly improving the electrochemical properties and inhibiting the adverse reaction. Expectedly, the 10 wt % LiV3O8/polydiphenylamine composite delivers a high initial specific discharge capacity of 311 mAh g–1, which decreases to 272 mAh g–1 after 50 cycles at the current density of 60 mA g–1. Even at a high current density of 2000 mA g–1, it still exhibited a reversible specific capacity of 125 mAh g–1 after 50 cycles. Quantitative kinetics analysis confirms the fundamental reasons for the enhanced rate capability. The ex situ X-ray diffraction and scanning electron microscopy results suggest that 10 wt % LiV3O8/polydiphenylamine composite possesses an ultrahigh structural stabilit...

Development of novel cathode materials for sodium-ion batteries with high capacity and excellent cyclic performance is an exciting and demanding research direction. Herein, we demonstrate the synthesis of NaV3O8 via a rheological phase reaction method. The crystal structure and morphology of synthesized NaV3O8 were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The NaV3O8 powder, calcined at moderate temperature (350 °C) with more uniform and smaller nanorod/nanoplate morphology, and larger d001 spacing, exhibited excellent electrochemical performance as cathode material in sodium ion batteries. A specific discharge capacity of 120 mAh g−1 was achieved at the current density of 120 mA g−1, with exceptional cyclic performance (discharge capacity of 95 mAh g−1 at the 500th cycle). In addition, the NaV3O8 cathode demonstrated excellent rate capability and delivered specific capacity of 80.8 mAh g−1 at current density of 300 mA g−1. The superior electrochemical performance corresponds to the structural stability and faster ionic diffusion. The preliminary results indicate that NaV3O8 can be an alternative cathode material for high-performance sodium-ion batteries.

The mechanical behavior and oxidation resistance of SiC/SiC-SiBC composites were studied in this work. According to the debonding criterion of He and Hutchinson, the debonding could occur at the BN interphase, which insures that the fibers can well play the strengthening and toughening performance. The oxidation resistance of SiC/SiC-SiBC composites consisting of SiC fibers with thermal expansion coefficients (CTE) of 5.1 × 10 −6 K −1 and 4.0 × 10 −6 K −1 was compared. The composites consisting of SiC fibers with higher CTE show slight weight changes at 800, 1000, and 1200 °C, and the corresponding strength retention ratios are 109.6%, 103.2% and 102.9%, exhibiting excellent oxidation resistance. The CTE of composites consisting of SiC fibers with higher CTE matches well with the CTE of SiC coating, so rarely no cracks can be formed in the coating, which inhibits the inward diffusion of oxidizing medium and leads to high strength retention ratios after oxidation tests.

The development of lithium-ion batteries is hindered by the lack of appropriate low-cost cathode materials with high performance. Here, the preparation of Cu-coated Li3V2(PO4)3/C (x% Cu-LVPC) composites is reported via a chemical precipitation and self-reduction method. With an optimized Cu coating content of 2.0 wt%, the 2.0% Cu-LVPC composite displays the best electrochemical properties. The initial discharge capacity of 2.0% Cu-LVPC is 175 mA h g−1 at 0.15 C (30 mA g−1) in the voltage range from 3.0 to 4.8 V and the capacity retention is 86.3% after 50 cycles, whereas pristine LVPC has an initial capacity of 163 mA h g−1 and retains 82.2% of the capacity after 50 cycles. Moreover, the rate capacity of 2.0% Cu-LVPC is also increased under different current densities and 2.0% Cu-LVPC exhibits excellent long-term cycling performance of 89 mA h g−1 after 1000 cycles at 10 C. The enhanced electrochemical properties are attributed to the uniform coating of the metal conductor Cu on the LVPC surface, which is conducive to electron transfer and extraction/insertion of Li+ ions.

In this paper, a new resin (PIDTR) containing acyl and thiourea chelating groups was synthesized and its adsorption performances and mechanism to Cu(II) were investigated by adsorption tests, BET, SEM, FTIR and XPS analyses. Equilibrium data were fitted well with Langmuir model with the maximum adsorption capacity of 1.1608 mmol g−1 for Cu(II) at pH 5.0. The regeneration and reusability test showed that the adsorption capacities decreased from 0.917 mmol g−1 to 0.88 mmol g−1 after five cycles of adsorption and desorption. The thermodynamics showed that the adsorption process was spontaneous and endothermic. The adsorption dynamic demonstrated that two stages in the adsorption process: liquid film diffusion and chemical adsorption. The studies of SEM indicated that Cu(II) ions were adsorbed on the surface of PIDTR. FTIR and XPS analysis further proved that Cu(II) ions were chemisorbed on the surface of PIDTR by formation of Cu N, Cu O and Cu S bonds with the breakage of N H, C=O and S=C bonds in PIDTR.

In this paper, an acyl-thiourea resin (PIDTR) was synthesized and its adsorption performances to Pb(II) were investigated by adsorption tests, scanning electron microscopy (SEM), Fourier transform ...

LiV 3 O 8 /poly (3, 4-ethylenedioxythiophene) (LVO/PEDOT) composites were synthesized via an in-situ oxidative polymerization process. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, galvanostatic discharge/charge tests, and electrochemical impedance spectroscopy techniques are used to characterize the as-prepared samples. The results demonstrated that the electrochemical performances of LVO/PEDOT composites have greatly improved in comparison with bare LVO. The discharge capacities of 20 wt% LVO/PEDOT composite are 270, 265, 252, 240, and 229 mAh g − 1 and ˃95% capacity retention is maintained after the charge-discharge 50 cycles at the current densities of 60, 90, 120, 180, and 240 mA g − 1 , respectively. A high reversible capacity of 176 mAh g − 1 (only 58 mAh g − 1 for the bare LVO) can be maintained after 50 cycles at a very high current rate of 2000 mA g − 1 . Electrochemical impedance spectra results implied that the 20 wt% LVO/PEDOT composite revealed a decreased charge transfer resistance and increased Li + ions diffusion ability. This noteworthy improvement is ascribed to the combination of PEDOT, which can act just as a defending layer to inhibit the LVO from direct contact with electrolyte and buffer volume change, and act just as a conductive network to improve the electronic conductivity, thus cycling stability and rate capability are improved.

LiV 3 O 8 /10 wt% poly(1,5-diaminoanthraquinone) composite was prepared by a in situ chemical oxidative polymerization process and applied as cathode material for rechargeable lithium batteries. Due to the introduction of poly(1,5-diaminoanthraquinone) and electrochemical synergistic effect, the composite demonstrated better rate capabilities and cycling performances compared to the bare LiV 3 O 8 sample.

One-dimensional Sb2Se3/C rods are prepared through self-assembly by inducing anisotropy, and their corresponding sodium storage behaviors are evaluated, presenting excellent electrochemical performances with superior cycling stability and rate capability. Sb2Se3 delivers a high initial charge capacity of 657.6 mA h g–1 at a current density of 0.2 A g–1 between 2.5 and 0.01 V. After 100 cycles, the reversible capacity of Sb2Se3/C is still retained at 485.2 mA h g–1. Even at a high rate current density of 2.0 A g–1, the charge capacity is still retained at 311.5 mA h g–1. Through the analysis of cyclic voltammetry and in situ electrochemical impedance spectroscopy, the in-depth understanding of high rate performances is explored effectively. Briefly, the sodium storage performance of Sb2Se3/C is observably enhanced, benefiting from the 1D structure and the introduction of a carbon layer with robust structure stability and conductivity.

An ultrasensitive sandwich-type electrochemical biosensor for microRNA (miRNA) detection is developed based on magnesium oxide (MgO) nanoflower and graphene oxide–gold nanoparticles (GO–AuNPs) hybrids coupling with electrochemical–chemical–chemical (ECC) detection system. In this bioassay system, MgO nanoflowers and AuNPs are modified on electrode to act as sensing platform. The thiolated capture probe is then self-assembled onto AuNPs/MgO substrate via formation of Au-S bonds. Subsequently, a biotinylated DNA signal probe is conjugated to GO–AuNPs hybrids. When miRNA-21 is added, a sandwich complex is formed and a lot of signal indicators streptavidin-conjugated alkaline phosphatases (SA-ALP) are immobilized upon electrode by the specific reaction between avidin and biotin. Finally, ECC reaction is performed in the system to improve detection signal. The proposed sandwich-type assay benefits from advantages of sandwich-type structure for enhanced sensitivity and specificity, MgO nanoflowers/AuNPs as sensing platform and GO–AuNPs hybrids as signal carriers for signal amplification, and ECC as a sensitive detection system for low detection limit. This biosensor exhibits a good dynamic ranging from 0.1 to 100 fM and a low detection limit of 50 aM (S/N = 3) toward target miRNA-21.

A class of linear impulsive fuzzy dynamic equations on time scales is considered by using the generalized differentiability concept on time scales. Some novel criteria and general forms of solutions are established for such models whose significance lies in proposing the possibility to get unifying forms of solutions for discrete and continuous dynamical systems under uncertainty and to unify corresponding problems in the framework of fuzzy dynamic equations on time scales. Finally, some examples show the applicability of our results.

A multifunctional G-PyB/KCl hydrogel showed outstanding self-healability, high conductivity, and rapid room-temperature phase-selective gelation capacity, and was developed as an electrochemical aptamer sensing platform for the ultrasensitive detection of alpha-fetoprotein.

The on-surface synthesis of single-layered covalent organic frameworks (sCOFs) has been investigated by employing a 3-fold symmetric monomer 1 carrying aldehyde groups and the ditopic diamine building block 2 on a highly oriented pyrolytic graphite surface. The self-assembly of molecule 1 is persistently observed at the stoichiometric ratio of the reactive groups. The growth of sCOF network is observed, however, only at the excess of diamine monomers. By investigating the growth process of the sCOF network, the role of excessive diamine monomers can be understood by two aspects. Increasing the molar ratio of diamine monomer provides the driving force for the structural transition from the monomer self-assembly to the formation of the sCOF network. On the other hand, the excess diamine monomers provide basic environment for the transimination reaction and promote the formation of highly ordered sCOFs. The present work provides molecular understanding of the role of transimination reaction in imine-based COF synthesis.

In this study, Ag2V4O11 was employed as an additive to boost the electrochemical performance of Li4Ti5O12. A series of Li4Ti5O12/Ag2V4O11 composites with different Ag2V4O11 mass ratios of 3 wt.%, 5 wt.% and 8 wt.% were prepared using liquid-phase dispersion method to yield compounds abbreviated as Li4Ti5O12/Ag2V4O11 (3 wt.%), Li4Ti5O12/Ag2V4O11 (5 wt.%) and Li4Ti5O12/Ag2V4O11 (8 wt.%), respectively. Among them, Li4Ti5O12/Ag2V4O11 (5 wt.%) composite displayed a considerable initial discharge specific capacity of 252.4 mAh g−1 at 30 mA g − 1 which still maintained at 152.0 mAh g−1 over 500 cycles. At 1200 mA g−1, a capacity of 69.0 mAh g−1 was retained over 5,000 cycles. The electrode kinetic studies revealed that the introduction of Ag2V4O11 phase boosted the transport rate of lithium ion and the electronic conductivity of Li4Ti5O12. In-situ XRD tests related that Ag2V4O11 was decomposed to in situ produce metallic Ag on Li4Ti5O12 after cycle. In a word, Li4Ti5O12/Ag2V4O11 (5 wt.%) composite was a promising as the electrode material in lithium-ion batteries. The data also provided a fire-new method to enhance the electrochemical property of Li4Ti5O12.

Adding Cu2+ has substantially boosted the practical potentiality of Fe/Mn-based layered cathodes for sodium ion batteries (SIBs) owing to the enhanced stabilities, which were previously ascribed to the raised valence of Mn. Herein, the roles of Cu2+ are verified by investigating Cu2+-substituted materials with the stoichiometry of Na0.5+xCuxFe0.5-xMn(IV)0.5O2. Surprisingly, it is found that Mn valence can hardly reach the expected value (IV) even by adjusting Cu2+ content. For the first time, the separation of CuO, which has been previously detected but rarely explained, is ascribed to the restrained chemical states of Mn. Detailed analyses show that, Mn(II) is generated while Mn(III) is decreased in pace of Cu2+ substitution, actually lowering down the oxidation states of Mn. Moreover, Mn4+/3+ redox can be efficiently restricted by importing Cu2+. Albeit the loss of capacity, the cycling stability is greatly enhanced, achieving a high capacity retention of 92.3% after 200 cycles within 4.2–2.5 V. Therefore, the suppression of Jahn-Teller Mn(III) should be intrinsically responsible for the superior cycling stability after Cu2+ substitution. These findings may present a new sight to probe the roles of Cu in layered NaxMO2 system for the design of advanced cathodes for SIBs.

Hollow-sphere ZnSe is successfully obtained through Ostwald ripening. Carbon nanoparticles are designed and utilized to form a wrapped carbon network as a conductive buffering matrix by subsequent annealing. The ZnSe/C composites, as anode materials for lithium-ion batteries (LIBs), exhibit excellent Li+ storage properties, delivering a high reversible capacity of 573.7 mA h g−1 at 1.0 A g−1 after 800 cycles. Even upon increasing the high current density to 20.0 A g−1, the reversible capacity can achieve 318.8 mA h g−1 after 5000 cycles. The superior rate capability is confirmed through the current density return from 20.0 to 1.0 A g−1, and ZnSe/C composites still recover up to 469 mA h g−1, with a retention of 92%. The enhanced electrochemical performances of ZnSe/C composites are attributed to the unique structure and the introduction of conductive carbon networks, which can improve the Li+ diffusion coefficient in the insertion and extraction process. Furthermore, the interconnected network also alleviates the volume variation during cycling and further enhances the structural stability.

Extensive efforts have been put into developing new materials with a 3D hollow porous spherical structure for increasing their applications in energy storage. In this work, 3D hollow porous carbon microspheres (3DHPCMs) are firstly prepared by the carbonization and post acid-treatment of 3D hollow microspherical Mn-MOFs (3DMn-MOFs), showing a high surface area of 788.2 m2 g−1 and a diameter of about 2 μm. Importantly, this is the first time that the conversion from 1D nanorods to 3D hollow spheres of Mn-MOFs through regulating the amount of poly(vinylpyrrolidone) (PVP) has been realized. Besides, the sodium storage behavior of 3D hollow porous carbon microspheres is also firstly studied. When utilized as anodes for sodium ion batteries (SIBs), the 3DHPCMs deliver excellent electrochemical storage performances with a high specific capacity of 313.8 mA h g−1 at a current density of 100 mA g−1. Impressively, a high discharge specific capacity of 112.5 mA h g−1 is obtained at 5 A g−1. The outstanding electrochemical performances can be attributed to the 3D hollow porous microsphere structure, which can enhance the mechanical stability, buffer the volume expansion, and accelerate the transport of Na+ and electrons. This work provides a new route for the development of materials with a 3D hollow spherical structure.

Restricted by their high specific surface area and porous structures, activated carbon (AC) materials display poor performances, such as a low initial coulombic efficiency in sodium-ion batteries (SIBs). Nevertheless, it is an ideal choice for carriers, where the high specific surface area is indispensable. Herein, a novel strategy to design S-doped carbon employing durian shell-based AC (DSAC) as the template is proposed and the effect of the amount of DSAC additive was investigated in detail. Impressively, an optimized amount of DSAC additive would contribute to the good dispersion of poly-2-thiophenemethanol (sulfur source) as well as an increased number of active sites for Na storage, thus resulting in excellent electrochemical performance. A high reversible specific capacity of 345 mA h g−1 was attained and the specific capacity of 264 mA h g−1 was retained after 200 cycles. In particular, a high initial coulombic efficiency of 56.02% and remarkable rate capability of 100.02 mA h g−1 were achieved at 5 A g−1 even after 4500 cycles. Meaningfully, the proposed route used to prepare carbon materials for SIBs can effectively facilitate the further application of AC and the construction of high-performance electrode materials for SIBs.