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1.
Small ; 20(23): e2309097, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38183380

RESUMO

The introduction of battery-type cathode has been commonly considered a preferred approach to boost the energy density of aqueous hybrid energy storage devices (AHESDs) in alkalic systems, but AHESDs with both high energy density and power density are rare due to the great challenge in designing battery-type anode materials with high rate and durability comparable to capacitive-type carbon anodes. In this paper, a well-hydrated iron selenate (FeSeO) sheath is constructed around FeOOH nanorods by a facile electrochemical activation, demonstrating the unique multifunction in fasting charge diffusion, promoting the dissociation of H2O, and inhibiting the irreversible phase transition of FeOOH to inert γ-Fe2O3, which endow the hydrated sheath coated Fe-based anodes with an impressive rate capability and superior durability. Thanks to the comprehensive performance of this Fe-based anode, the assembled AHESD delivered a high energy density of 117 Wh kg-1 with the extraordinary durability of almost 100% capacity retention after 40 000 cycles. Even at an ultrahigh power density of 27 000 W kg-1, an impressive energy density of 65 Wh kg-1 can be achieved, which rivals previously reported energy-storage devices.

2.
Phys Chem Chem Phys ; 26(21): 15221-15231, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38745551

RESUMO

In asymmetric supercapacitors, transition metal selenates are promising electrodes, but their capacity are limited by a single redox center. To further enhance the performance of transition metal selenates, NixCo1-xSeO3 (NCSeO) doped with N and Cl was prepared on nickel-plated carbon cloth (NCSeO-NCl-NiCC). During electrochemical reactions, NCSeO can be converted to M(OH)2 (M = Ni/Co) and OH- is replaced by N and Cl. Two redox centers, M(OH)2/MOOH and M(OH)xN2-x/NO3-, are formed during charging and discharging, which is attributed to the increased capacity of the NCSeO-NCl-NiCC electrode. On NCSeO, the substitution of Cl facilitates the regulation of the electronic structure and enhances the stability of N-doping. The optimised electrode exhibits a high capacity of 417 mA h g-1 at 1 A g-1 and an impressive rate capability of 235 mA h g-1 at 50 A g-1. Asymmetric supercapacitors with this design have an ultra-high energy density of 73.6 W h kg-1, as well as an excellent rate and cycling performance with a capacitance retention of 97.8% after 20 000 cycles at a current density of 20 A g-1.

3.
Phys Chem Chem Phys ; 25(13): 9104-9114, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36928112

RESUMO

Flexible aqueous supercapacitors are promising candidates as safe power sources for wearable electronic devices (WEDs). However, the absence of advanced electrode materials with high structural stability has become the most critical factor hindering the development, which is closely related to the poor interface combination between the active substances and flexible collectors. Herein, a unique rigid layered double hydroxide (LDH) nanorod array with the mesocrystalline feature is created using the NiO-Ni layer as the inducer by the electrodeposition strategy. Differing from the traditional NiCo-LDH nanosheets directly grown on a carbon cloth, an elaborately designed NiO-Ni buffer can simultaneously and effectively improve the bidirectional combination with active substances and collectors, also the mesocrystalline LDH showed enhanced intrinsic stability through the reinforcing effect of grain boundaries. Benefiting from these, the assembled supercapacitor exhibited pre-eminent cycle stability (increased from 64% of the initial capacity after 10 000 cycles to no significant attenuation after 50 000 cycles) and ultrahigh energy density. When it was used as a flexible device, a remarkable energy density of 70.4 W h kg-1 could be harvested and processed with high flexibility in the bending state and good temperature adaptability. This study provides an excellent design strategy for the development of next-generation flexible supercapacitors with the goal of better comprehensive performances.

4.
Molecules ; 28(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37630334

RESUMO

In order to obtain homogeneous Sanghuangporus vaninii polysaccharides with antioxidant and anti-inflammatory activities, a response surface method (RSM) was used to compare the polysaccharide extraction rate of hot water extraction and ultrasonic-assisted extraction from Sanghuangporus vaninii. The optimal conditions for ultrasonic-assisted extraction were determined as follows: an extraction temperature of 60 °C, an extraction time of 60 min, a solid-liquid ratio of 40 g/mL, and an ultrasonic power of 70 W. An SVP (Sanghuangporus vaninii polysaccharides) extraction rate of 1.41% was achieved. Five homogeneous monosaccharides were obtained by gradient ethanol precipitation with diethylaminoethyl-cellulose (DEAE) and SephadexG-100 separation and purification. The five polysaccharides were characterized by high performance liquid chromatography, the ultraviolet spectrum, the Fourier transform infrared spectrum, TG (thermogravimetric analysis), the Zeta potential, and SEM (scanning electron microscopy). The five polysaccharides had certain levels of antioxidant activity in vitro. In addition, we the investigated the anti-inflammatory effects of polysaccharides derived from Sanghuangporus vaninii on lipopolysaccharide (LPS)-induced RAW 264.7 cells and Kupffer cells. Further, we found that SVP-60 significantly inhibited the levels of pro-inflammatory cytokines, such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α in lipopolysaccharide (LPS)-induced RAW 264.7 cells and promoted the level of the anti-inflammatory cytokine IL-10 in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Our study provides theoretical support for the potential application of Sanghuangporus vaninii in the field of antioxidant and anti-inflammatory activities in vitro.


Assuntos
Antioxidantes , Lipopolissacarídeos , Antioxidantes/farmacologia , Polissacarídeos/farmacologia , Anti-Inflamatórios/farmacologia , Citocinas
5.
J Ethnopharmacol ; 319(Pt 3): 117284, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37844741

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: Sanghuangporus vaninii (S. vaninii), as a traditional large medicinal fungus, has a history of more than 2000 years in Chinese history and has been widely used to treat female diseases such as vaginal discharge, amenorrhea, and uterine bleeding, and recent pharmacological studies have also found that it has antioxidant, anti-inflammatory, and anti-tumor physiological activity, which has received more and more attention. AIM OF THE STUDY: The objective was to evaluate cytotoxicity and the acute, subacute toxicity, and in vitro antioxidant activity of S. vaninii crude polysaccharide (SVP). MATERIALS AND METHODS: The monosaccharide composition of SVP was determined by HPLC (high-performance liquid chromatography). The cytotoxicity of different concentrations of SVP on three types of cells (HT-22, Kupffer macrophages, HEK293) was assessed using CCk-8. The acute toxicity in vivo was evaluated for 14 days after the administration of SVP (2500,5000, or 10,000 mg/mL). For the evaluation of subacute toxicity, mice were daily treated for 28 days with SVP (2500,5000, or 10,000 mg/mL). In addition, DPPH, hydroxyl radical, and superoxide anion radical were used to evaluate the in vitro antioxidant activity of SVP. RESULTS: SVP was not toxic in all three cell lines tested. In vitro antioxidant tests on the extracts showed that SVP possessed a strong antioxidant capacity in vitro. In the acute study, the no-observed-adverse-effect level (NOAEL) in male and female rats was 10,000 mg/kg body weight. There were also no deaths or severe toxicity associated with SVP in subacute studies. However, SVP treatment had a decreasing effect on body weight in mice of both sexes (2500, 5000, and 10000 mg/kg). At doses (5000 and 10,000 mg/kg), SVP had a reduced effect on food intake in both male and female mice. In addition, there were significant effects on organ coefficients of the liver, lung, and kidney. Hematological analysis showed significantly lower LYM (%) values in mice of both sexes, with significantly lower MCH (pg) values obtained in males (5000 mg/kg and 10000 mg/kg) and higher GRAN (%) values in females. In addition, the RDW-SD (fL) values were significantly lower in the male mice given the highest dose. Biochemical tests showed that there were no significant changes in ALT, AST, TP, and Cr levels after SVP treatment. In histopathological analysis, mild liver toxicity was observed in both female mice treated with 10,000 mg/kg SVP. CONCLUSION: The extract of SVP showed a predominance of polysaccharide compounds, with non-toxic action in vivo. Our approach revealed SVP on the chemical composition and suggests a high margin of safety in the popular use of medicinal fungi. In conclusion, our results suggest that SVP is safe, and can be used as health care products and food.


Assuntos
Antioxidantes , Extratos Vegetais , Ratos , Camundongos , Humanos , Masculino , Feminino , Animais , Antioxidantes/toxicidade , Extratos Vegetais/toxicidade , Células HEK293 , Testes de Toxicidade Aguda , Peso Corporal
6.
Chemosphere ; 340: 139736, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37544526

RESUMO

Intramolecular-tailored graphite carbon nitride (g-C3N4) has great potential to greatly optimize the photo-response performance and carrier separation ability, but exquisite molecular structure engineering is still challenging. Firstly, a series of oxygen and terminal methyl moiety co-modified g-C3N4 (CNNx) has been systematically prepared by using N-Hydroxysuccinimide (HOSu) as a novel copolymerized precursor and urea. The density functional theory (DFT) calculations demonstrated that the presence of oxygen can lower the binding energy for the C-C bond to make the terminal modification easier. The terminal methyl and Oxygen not only caused abundant alveolar defects to break the periodic symmetry but also acted as an electron-accepting platform to tune the local charge redistribution within g-C3N4 molecular. The synthesized CNNx (CNN25) achieved ultra-high photocatalytic activity and chemical stability under visible light toward antibiotic degradation (99% tetracycline, 92% doxycycline, 65% ofloxacin and 74% sulfathiazole degradation within 30 min) and hydrogen production (an apparent quantum efficiency of 2.10% at 400 nm). CNN25 also maintains good efficiency in surface water and groundwater. Moreover, the TC solution treated with CNN25 had hardly any harm to the growth of E. coli. We believe our findings will provide a facile and green strategy for the preparation of non-metallic modified g-C3N4.


Assuntos
Grafite , Grafite/química , Escherichia coli , Antibacterianos , Luz , Hidrogênio , Catálise
7.
Adv Mater ; 35(41): e2303360, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37494282

RESUMO

Fe-based battery-type anode materials with many faradaic reaction sites have higher capacities than carbon-based double-layer-type materials and can be used to develop aqueous supercapacitors with high energy density. However, as an insurmountable bottleneck, the severe capacity fading and poor cyclability derived from the inactive transition hinder their commercial application in asymmetric supercapacitors (ASCs). In this work, driven by the "oxygen pumping" mechanism, oxygen-vacancy-rich Fe@Fe3 O4 (v) @Fe3 C@C nanoparticles that consist of a unique "fruit with stone"-like structure are developed, and they exhibit enhanced specific capacity and fast charge/discharge capability. Experimental and theoretical results demonstrate that the capacity attenuation in conventional iron-based anodes is greatly alleviated in the the Fe@Fe3 O4 (v) @Fe3 C@C anode because the irreversible phase transition to the inactive γ-Fe2 O3 phase can be inhibited by a robust barrier formed by the coupling of oxygen vacancies and Fe─C bonds, which promotes cycle stability (93.5% capacity retention after 24 000 cycles). An ASC fabricated using this Fe-based anode is also observed to have extraordinary durability, achieving capacity retention of 96.4% after 38 000 cycles, and a high energy density of 127.6 W h kg-1 at a power density of 981 W kg-1 .

8.
ACS Appl Mater Interfaces ; 15(3): 4081-4091, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36635877

RESUMO

The central goal of high-performance potassium ion storage is to control the function of the anode material via rational structural design. Herein, N- and S-doped hollow carbon spheres with outer-short-range-order and inner-disorder structures are constructed to achieve highly efficient and ultra-stable potassium ion storage using a low-temperature molten salt system. The ultrathin carbon walls and uniform mesoporous as well as unique heterostructure synergistically realize significant potassium storage performance via facilitating rapid diffusion of potassium ions and alleviating substantial volume expansion. Furthermore, as the anode of a potassium ion battery, the as-prepared MSTC electrode demonstrates a state-of-the-art cycling capability of 221.3 mAh g-1 at 1 A g-1 after 20,000 cycles. The assembled potassium ion hybrid capacitor device demonstrates a high energy of 157 Wh kg-1 at 956 W kg-1 and excellent reversibility at a current density of 5.0 A g-1 after 20,000 cycles with 82.7% capacity retention. Accordingly, our work provides new ideas for designing advanced carbon anode materials and understanding the charge storage mechanism in potassium ion battery, as well as constructing high energy-power density potassium-ion hybrid capacitors (PIHCs).

9.
Small Methods ; 7(3): e2201353, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36651131

RESUMO

Transitional metal chalcogenide (TMC) is considered as one promising high-capacity electrode material for asymmetric supercapacitors. More evidence indicates that TMCs have the same charge storage mechanism as hydroxides, but the reason why TMC electrode materials always provide higher capacity is rare to insight. In this work, a Nix Coy Mnz S/Ni(SeO3 ) (NCMS/NSeO) heterostructure is prepared on Ni-plated carbon cloth, validating that both NCMS and NSeO can be transformed into hydroxides in electrochemical process as accompanying with the formation of SeO3 2- and SOx 2- in confined spaces of NCMS/NSeO/Ni sandwich structure. Based on density functional theory calculation and experimental results, a novel space-confined acidic radical adsorption capacity-activation mechanism is proposed for the first time, which can nicely explain the capacity enhancement of NCMS/NSeO electrode materials. Thanks to the unique capacity enhancement mechanism and stable NCMS/NSeO/Ni sandwich structure, the optimized electrodes exhibit a high capacity of 536 mAh g-1 at 1 A g-1 and the impressive rate capability of 140.5 mAh g-1 at the amazing current density of 200 A g-1 . The assembled asymmetric supercapacitor achieves an ultrahigh energy density of 141 Wh Kg-1 and an impressive high-rate capability and cyclability combination with 124% capacitance retention after 10 000 cycles at a large current density of 50 A g-1 .

10.
Environ Sci Pollut Res Int ; 29(54): 82271-82285, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35750907

RESUMO

The development of urbanization has changed the original land cover and exacerbated the urban heat island effect, seriously affecting the sustainable development of the ecological environment. Research on urban heat island characteristics and land cover changes in five major urban agglomerations in China to provide a reference for preventing thermal environmental risks and urban agglomeration construction planning. This paper estimates the surface urban heat island intensity (SUHII) of the five major urban agglomerations in China from 2003 to 2019 based on Google Earth Engine (GEE) through the urban-rural dichotomy, analyzes their trends through the Sen + M-K trend analysis method, and combines the detrending rate matrix to analyze the impact of land cover type shift on urban heat island change. Research shows that (1) the land cover types of the five major urban agglomerations in China have changed considerably from 2003 to 2019, and all five major urban agglomerations in China experienced varying degrees of urban expansion. (2) The annual average value of SUHII decreases in Beijing-Tianjin-Hebei, Yangtze River Delta, and middle reaches of the urban agglomerations, while the annual average value of SUHII increases in Chengdu-Chongqing and Pearl River Delta urban agglomerations. (3) The spatial composition of land cover types in the five major urban agglomerations in China is highly spatially correlated with urban heat islands, with urban land and bare land urban heat islands being the most pronounced. (4) The land cover type shift has the most significant heat island impact on Beijing-Tianjin-Hebei, Yangtze River Delta, and Chengdu-Chongqing urban agglomerations. (5) The land cover change (LCC) with an increasing trend in SUHII is mainly bare land converted to arable land, and water bodies, grassland, forest land, and arable land converted to urban land.


Assuntos
Temperatura Alta , Urbanização , Cidades , China , Água
11.
Insects ; 12(2)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494404

RESUMO

Leptocybe invasa is a globally invasive pest of eucalyptus plantations, and is steadily spread throughout China. Predicting the growth area of L. invasa in China is beneficial to the establishment of early monitoring, forecasting, and prevention of this pest. Based on 194 valid data points and 21 environmental factors of L. invasa in China, this study simulated the potential distribution area of L. invasa in China under three current and future climate scenarios (SSPs1-2.5, SSPs2-3.5, and SSPs5-8.5) via the MaxEnt model. The study used the species distribution model (SDM) toolbox in ArcGIS software to analyze the potential distribution range and change of L. invasa. The importance of crucial climate factors was evaluated by total contribution rate, knife-cut method, and environmental variable response curve, and the area under the receiver operating characteristic (ROC) curve was used to test and evaluate the accuracy of the model. The results showed that the simulation effect of the MaxEnt model is excellent (area under the ROC curve (AUC) = 0.982,). The prediction showed that L. invasa is mainly distributed in Guangxi, Guangdong, Hainan, and surrounding provinces, which is consistent with the current actual distribution range. The distribution area of the potential high fitness zone of L. invasa in the next three scenarios increases by between 37.37% and 95.20% compared with the current distribution. Climate change affects the distribution of L. invasa, with the annual average temperature, the lowest temperature of the coldest month, the average temperature of the driest season, the average temperature of the coldest month, and the precipitation in the wettest season the most important. In the future, the core areas of the potential distribution of L. invasa in China will be located in Yunnan, Guangxi, Guangdong, and Hainan. They tend to spread to high latitudes (Hubei, Anhui, Zhejiang, Jiangsu, and other regions).

12.
Insects ; 12(10)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34680643

RESUMO

The red imported fire ant, Solenopsis invicta (Hymenoptera: Formicidae), is an invasive pest, and it has spread rapidly all over the world. Predicting the suitable area of S. invicta growth in China will provide a reference that will allow for its invasion to be curbed. In this study, based on the 354 geographical distribution records of S. invicta, combined with 24 environmental factors, the suitable areas of S. invicta growth in China under current (2000s) and future (2030s and 2050s) climate scenarios (SSPs1-2.5s, SSPs2-3.5s and SSPs5-8.5s) were predicted by using the optimized MaxEnt model and geo-detector model. An iterative algorithm and knife-cut test were used to evaluate the important environmental factors that restrict the suitable area under the current climatic conditions. This study also used the response curve to determine the appropriate value of environmental factors to further predict the change and the center of gravity transfer of the suitable area under climate change. The optimized MaxEnt model has high prediction accuracy, and the working curve area (AUC) of the subjects is 0.974. Under climatic conditions, the suitable area is 81.37 × 104 km2 in size and is mainly located in the south and southeast of China. The main environmental factors affecting the suitable area are temperature (Bio1, Bio6, and Bio9), precipitation (Bio12 and Bio14) and NDVI. In future climate change scenarios, the total suitable area will spread to higher latitudes. This distribution will provide an important theoretical basis for relevant departments to rapidly prevent and control the invasion of S. invicta.

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