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1.
Adv Sci (Weinh) ; : e2401636, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38741379

ABSTRACT

Triboelectric nanogenerators (TENGs), a promising strategy for harvesting distributed low-quality power sources, face inevitable bottlenecks regarding long-term abrasion and poor durability. Herein, both issues are addressed by selecting an earthworm-inspired self-replenishing bionic film (ERB) as the tribo-material of sliding-freestanding TENGs (SF-TENGs), it consists of an interconnected 3D porous network structure capable of storing and releasing lubricant under cyclic mechanical stimuli. Thanks to the superiority of self-replenishing property, there is no need for periodic replenishment and accurate content control of lubricant over the interfacial-lubricating SF-TENGs based on dense tribo-layers. Additionally, an SF-TENG based on ERB film (ERB-TENG) demonstrates remarkable output stability with only a slight attenuation of 1% after continuous operation for 100 000 cycles. Moreover, the ERB-TENG displays a distinguished anti-wear property, exhibiting no distinct abrasion with an ultra-low coefficient of friction (0.077) and maintaining output stability over a prolonged period of 35 days. Furthermore, integration with an energy management circuit enables the ERB-TENG to achieve a 39-fold boost in charging speed. This work proposes a creative approach to enhance the durability and extend the lifespan of TENG devices, which is also successfully applied to wind energy harvesting and intelligent sports monitoring.

2.
Nano Lett ; 24(2): 688-695, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38180811

ABSTRACT

The effects of surface roughness on the performance of the Zn metal anode in aqueous electrolytes are investigated by experiments and computational simulations. Smooth surfaces can homogenize the nucleation and growth of Zn, which helps to form a flat Zn anode under high current density. In spite of these advantages, the whole surface of the smooth electrode serves as the reactive contact area for parasitic reactions, generating severe hydrogen evolution, corrosion, and byproduct formation, which seriously hinder the long-term cycle stability of the Zn anode. To trade off this double-sided effect, we identify a medium degree of surface roughness that could stabilize the Zn anode for 1000 h cycling at 1.0 mAh cm-2. The electrode also enabled stable cycling for 800 h at a high current density of 5.0 mAh cm-2. This naked Zn metal anode with optimized surface roughness holds great promise for direct use in aqueous zinc ion batteries.

3.
Chem Commun (Camb) ; 60(12): 1627-1629, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38232307

ABSTRACT

V2O5·nH2O is a promising cathode material for zinc-ion batteries. One of the synthesis methods of V2O5·nH2O is in situ self-transformation. In this communication, we focus on the influence of the electrolyte environment during in situ self-transformation (from VO2 to V2O5·nH2O). 2 M ZnSO4 and 2 M Zn(OTf)2 were used as different electrolytes to produce VOH-1 and VOH-2. VOH-1 expands in volume along the electric field to form a porous surface structure and shows low crystallinity along the (0 0 1) plane, while VOH-2 exhibits the opposite. These advantages enable the assembled batteries with VOH-1 to maintain excellent cycling performance at a rate of 2 A g-1 with a capacity of 500 mA h g-1 and stable cycling for 1800 cycles.

4.
Dalton Trans ; 53(7): 3356-3362, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38263884

ABSTRACT

In recent years, Bi3+ activated phosphors have received a lot of attention from researchers; however, the performance and application areas of phosphors are yet to be developed. In this work, a series of CaScBO4(CSBO):xBi3+ phosphors were successfully prepared using a high-temperature solid-state method. Under UV excitation, blue light emission was achieved at 430 nm with a quantum yield of 91%, and at 423 K, the emission intensity retained 82.8% of the original intensity at 298 K. By crystal field engineering, the substitution of Sr2+ at the Ca2+ site enhances the temperature stability of the material, and at 423 K, 473 K and 573 K, the samples maintain 104%, 103% and 85% of the emission intensity at room temperature, respectively. It indicates that the cation substitution causes the increase in the oxygen vacancy concentration, and the oxygen vacancy defect compensates the energy lost in electrons at high temperature, producing resistance to anti-TQ performance. Finally, a blue-violet LED was fabricated by using the phosphor and an ultraviolet LED chip, and white LEDs (CCT = 4683 K, Ra = 89.7) were obtained by co-packaging this phosphor with commercial phosphors and a UV chip. Importantly, the great potential of this phosphor in the field of plant lighting and biocontrol can be demonstrated.

5.
ACS Omega ; 9(2): 2088-2103, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38250373

ABSTRACT

To explore the sedimentary environment and the background of the source area of organic-rich shales in the Wufeng-Longmaxi Formations in the northern Sichuan Basin, samples from Well XX1 in the area were subjected to geochemical testing and analysis of organic carbon content, trace elements, and rare earth elements (REEs). The results show that the total content of REE (ΣREE) of the shale in the Wufeng-Longmaxi Formations varied from 183.08 to 234.66 µg/g with an average of 212.59 µg/g, which is significantly higher than the content of the North American shale composite. The fluctuations in the total amount of REEs in the shale of the Wufeng-Longmaxi Formations reflect certain differences in the geochemical conditions of the Upper Ordovician-Lower Silurian shale. The ratios of LREE/HREE, LaN/YbN, LaN/SmN, and GdN/YbN and the distribution of normalized REE patterns indicate that the source supply or sedimentary structural background may have changed during the shale deposition period of the Wufeng Formation, while the shale deposition period of the Longmaxi Formation may be in a relatively stable source supply and sedimentary structural background. There is no significant correlation between δCe and ΣREE, and the obviously negative Eu abnormity and the weak Ce abnormity indicated that the diagenesis had a limited impact on REEs. Geochemical parameters such as values of ∑REE, δEu, δCe, Ceanom, and LaN/YbN indicate that the climate during the Wufeng-Longmaxi Formation shale deposition period was warm and humid, and the shale was deposited mainly in the suboxic-anoxic water environment. The deposition rate was stable and slow, providing good conditions for the production and preservation of organic matter. At the same time, this shows that the water environment of Wufeng Formation is more anoxic and reductive than that of Longmaxi Formation, which is more conducive to the preservation of organic matter. The correlation between ΣREE and the content of Sc, Ti, Cr, Co, Zr, Nb, Th, Hf, Ta, and other elements indicates that the sources of REEs in the shale of Wufeng and Longmaxi Formations in the study area are similar, mainly terrestrial clasts, and some may come from the sea. The REE distribution pattern shows that the shale provenance of the Wufeng-Longmaxi Formations mainly comes from the upper crust. The La/Yb-∑REE diagram shows that the sediment-parent rocks are mainly early sedimentary rocks and these sediment-parent rocks have granite provenance characteristics. Compared to La/Yb, LREE/HREE, LaN/YbN, and other REE characteristic parameters, it is inferred that the tectonic background of the study area is dominated by passive continental margin.

6.
Adv Sci (Weinh) ; 11(7): e2305241, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38084003

ABSTRACT

Luminescent materials that display quick spectral responses to thermal stimuli have attracted pervasive attention in sensing technologies. Herein, a programmable luminescence color switching in lanthanide-doped LiYO2 under thermal stimuli, based on deliberate control of the monoclinic (ß) to tetragonal (α) phase transition in the crystal lattice, is reported. Specifically, a lanthanide-doping (Ln3+ ) approach to fine-tune the phase-transition temperature in a wide range from 294 to 359 K is developed. Accordingly, an array of Ln3+ -doped LiYO2 crystals that exhibit progressive phase transition, and thus sequential color switching at gradually increasing temperatures, is constructed. The tunable optical response to thermal stimuli is harnessed for colorimetric temperature indication and quantitative detection, demonstrating superior sensitivity and temperature resolution (Sr = 26.1% K-1 , δT = 0.008 K). The advances in controlling the phase-transition behavior of luminescent materials also offer exciting opportunities for high-performance personalized health monitoring.

7.
Nat Commun ; 14(1): 5940, 2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37741826

ABSTRACT

Accurate evaluation of Li-ion battery (LiB) safety conditions can reduce unexpected cell failures, facilitate battery deployment, and promote low-carbon economies. Despite the recent progress in artificial intelligence, anomaly detection methods are not customized for or validated in realistic battery settings due to the complex failure mechanisms and the lack of real-world testing frameworks with large-scale datasets. Here, we develop a realistic deep-learning framework for electric vehicle (EV) LiB anomaly detection. It features a dynamical autoencoder tailored for dynamical systems and configured by social and financial factors. We test our detection algorithm on released datasets comprising over 690,000 LiB charging snippets from 347 EVs. Our model overcomes the limitations of state-of-the-art fault detection models, including deep learning ones. Moreover, it reduces the expected direct EV battery fault and inspection costs. Our work highlights the potential of deep learning in improving LiB safety and the significance of social and financial information in designing deep learning models.

8.
Food Funct ; 14(11): 5196-5204, 2023 Jun 06.
Article in English | MEDLINE | ID: mdl-37191069

ABSTRACT

In this study, starch-polyphenol complexes (CES-TPS complexes) were prepared using various ratios (0%, 2%, 4%, 6%, 8%, and 10%, based on starch) of tea polyphenols (TPS) and high amylose corn starch (HACS) pretreated with starch branching enzyme (SBE). It was aimed to determine the effects of TPS on the physicochemical and structural properties and digestibility of the CES-TPS complexes. Scanning electron microscopy and laser particle size analysis showed that the addition of a moderate amount of TPS will reinforce interaction force, while excessive TPS will cause a loose structural morphology, leading to an increase in starch particle size. Thermal property analysis indicated that SBE pre-treatment decreased TO, TP and TC of HACS, and the gelatinization temperature was further reduced after adding TPS. The digestion of CES-TPS complexes was investigated using an Artificial Gut analyzer; the predicted glycemic index of starch samples decreased with the addition of a low concentration of TPS (2-6%), while there was a significant increment in the pGI of starch samples when a high concentration of TPS (8-10%) was added. XRD analysis showed that the relative crystallinity of the CES-TPS complexes further increased to 21.91% and then decreased to 19.38% with the increase of TPS concentration. The ratios of 1047/1022 cm-1 presented the opposite trend to that determined by FT-IR.


Subject(s)
Amylose , Starch , Starch/chemistry , Amylose/chemistry , Zea mays/chemistry , Spectroscopy, Fourier Transform Infrared , Polyphenols/chemistry , Tea/chemistry
9.
Carbohydr Polym ; 288: 119348, 2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35450621

ABSTRACT

Solution plasma process (SPP) was employed to degrade chitosan. The effects of the initial pH value and the distance between the electrodes on the steady shear flow behavior, structural characterization, molecular conformation, and antioxidant activity of chitosan were investigated. The results revealed that a lower initial pH value and a narrower distance between the electrodes were beneficial to the decrease in viscosity and increase in shear-thinning capacity. Structural characterization of the chitosan by FT-IR and 1H NMR showed that chemical structure of chitosan was not destroyed at different process parameters. The results of XRD, HPSEC-MALLS, SEM, and AFM indicated that SPP degradation clearly decreased the crystallinity, molecular weight, molecular size, and molecular aggregation of chitosan. At initial pH values of 2.8 and 5.8, the molecular weight was 27.16 and 44.25 kDa, at the distance between the electrodes of 4 and 8 mm, it was 35.88 and 66.17 kDa, respectively. The results of DPPH and hydroxyl radical scavenging assays demonstrated that a lower initial pH value and a narrower distance between the electrodes enhanced the antioxidant activity.


Subject(s)
Chitosan , Antioxidants/chemistry , Antioxidants/pharmacology , Chitosan/chemistry , Electrodes , Hydrogen-Ion Concentration , Spectroscopy, Fourier Transform Infrared
10.
Food Sci Nutr ; 10(3): 678-688, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35282008

ABSTRACT

The physicochemical properties of starch acetates with an equal degree of substitution prepared from pea, corn, and wheat starch and their effects on frozen cooked noodle (FCN) quality were investigated. The result showed that the three kinds of starch acetates had different effects on the quality of FCN due to their different blue values, freeze-thaw stability, and crystalline morphology analyzed by XRD (p < .05). The FCN with the addition of 20% CAS exhibited slow deterioration of textural properties during holding for 30 min. The analysis of the changes in the content of free SH group and glutenin macropolymer (GMP) demonstrated that the addition of CAS promoted protein disulfide cross-linking and decreased protein mobility during holding. Fourier transform infrared spectroscopy (FT-IR) revealed that FCN with the addition of CAS had low decrement in α-helix and ß-sheet during holding, indicating that starch acetates contributed to the maintenance of the gluten network structure.

11.
Int J Biol Macromol ; 183: 481-489, 2021 Jul 31.
Article in English | MEDLINE | ID: mdl-33933544

ABSTRACT

In this study, the effect of microwave-ultrasound or/and toughening treatment on the physicochemical, structural properties, and in vitro digestibility of A- and B-type granules isolated from wheat starch were investigated. From the SEM, microwave-ultrasound and toughening treatment (MU-T) led to the appearance of irregular and disrupted structure significantly and an increment in the resistant starch content of A- and B-type granule. Furthermore, the MU-T starch possessed the lowest swelling power, light transmittance, and gelatinization temperature range (Tc -To) and the highest ΔH. After MU-T, the relative crystallinity (RC) of X-ray pattern, Fourier transform infrared ratio of 1047/1022 cm-1, and the content of double helix and single helix of 13C CP/MAS NMR had increased significantly. In particular, there was a difference in the content of RS and SDS between A-starch granules and B-starch granules as well as their changes after modification (from 69.305% to 82.93 for A-starch and form 74.97% to 88.17 for B-starch, respectively), which was a similar trend with RC and helix content. This study indicated that, for both A-type granule and B-type granule starches, microwave-ultrasound and toughening treated samples had unique properties compared to singly modified starches.


Subject(s)
Amylose/metabolism , Digestion , Food Handling , Microwaves , Resistant Starch/metabolism , Triticum/enzymology , Ultrasonics , Amylose/chemistry , Carbohydrate Conformation , Hydrolysis , Resistant Starch/analysis , Triticum/chemistry
12.
iScience ; 24(1): 101921, 2021 Jan 22.
Article in English | MEDLINE | ID: mdl-33409473

ABSTRACT

Heating battery at low temperatures is fundamental to avoiding the range anxiety and the time-consuming charging associated with electric vehicles (EVs). One method for achieving fast and uniform battery heating is to polarize the cell under pulse currents. However, the on-board implementation of this method leads to an increase in the cost and size. Therefore, in this study, an adapted EV circuitry compatible with the existing one and an optimized operating condition are proposed to enable rapid battery heating. With this circuit, electricity transfer between the cells can be realized through a motor, leading to remarkably higher battery currents than those of the conventional circuit. The increase in the maximum heating currents (from 1.41C to 4C) resulted in a battery temperature rise of 8.6°C/min at low temperatures. This heating method exhibits low cost, high efficiency, and negligible effects on battery degradation, practical and promising on battery heating of EVs.

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