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1.
Nanomicro Lett ; 16(1): 164, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546948

RESUMO

Aqueous Zn2+-ion batteries (AZIBs), recognized for their high security, reliability, and cost efficiency, have garnered considerable attention. However, the prevalent issues of dendrite growth and parasitic reactions at the Zn electrode interface significantly impede their practical application. In this study, we introduced a ubiquitous biomolecule of phenylalanine (Phe) into the electrolyte as a multifunctional additive to improve the reversibility of the Zn anode. Leveraging its exceptional nucleophilic characteristics, Phe molecules tend to coordinate with Zn2+ ions for optimizing the solvation environment. Simultaneously, the distinctive lipophilicity of aromatic amino acids empowers Phe with a higher adsorption energy, enabling the construction of a multifunctional protective interphase. The hydrophobic benzene ring ligands act as cleaners for repelling H2O molecules, while the hydrophilic hydroxyl and carboxyl groups attract Zn2+ ions for homogenizing Zn2+ flux. Moreover, the preferential reduction of Phe molecules prior to H2O facilitates the in situ formation of an organic-inorganic hybrid solid electrolyte interphase, enhancing the interfacial stability of the Zn anode. Consequently, Zn||Zn cells display improved reversibility, achieving an extended cycle life of 5250 h. Additionally, Zn||LMO full cells exhibit enhanced cyclability of retaining 77.3% capacity after 300 cycles, demonstrating substantial potential in advancing the commercialization of AZIBs.

2.
Angew Chem Int Ed Engl ; 63(11): e202318928, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38189767

RESUMO

The Zn//V2 O5 system not only faces the incontrollable growth of zinc (Zn) dendrites, but also withstands the cross-talk effect of by-products produced from the cathode side to the Zn anode, inducing interelectrode talk and aggravating battery failure. To tackle these issues, we construct a rapid Zn2+ -conducting hydrogel electrolyte (R-ZSO) to achieve Zn deposition modulation and side reaction inhibition in Zn//V2 O5 full cells. The polymer matrix and BN exhibit a robust anchoring effect on SO4 2- , accelerating Zn2+ migration and enabling dense Zn deposition behavior. Therefore, the Zn//Zn symmetric cells based on the R-ZSO electrolyte can operate stably for more than 1500 h, which is six times higher than that of cells employing the blank electrolyte. More importantly, the R-ZSO hydrogel electrolyte effectively decouples the cross-talk effects, thus breaking the infinite loop of side reactions. As a result, the Zn//V2 O5 cells using this modified hydrogel electrolyte demonstrate stable operation over 1,000 cycles, with a capacity loss rate of only 0.028 % per cycle. Our study provides a promising gel chemistry, which offers a valuable guide for the construction of high-performance and multifunctional aqueous Zn-ion batteries.

3.
Small ; 20(1): e2305030, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37649169

RESUMO

Vanadium-based oxides have attracted much attention because of their rich valences and adjustable structures. The high theoretical specific capacity contributed by the two-electron-transfer process (V5+ /V3+ ) makes it an ideal cathode material for aqueous zinc-ion batteries. However, slow diffusion kinetics and poor structural stability limit the application of vanadium-based oxides. Herein, a strategy for intercalating organic matter between vanadium-based oxide layers is proposed to attain high rate performance and long cycling life. The V3 O7 ·H2 O is synthesized in situ on the carbon cloth to form an open porous structure, which provides sufficient contact areas with electrolyte and facilitates zinc ion transport. On the molecular level, the added organic matter p-aminophenol (pAP) not only plays a supporting role in the V3 O7 ·H2 O layer, but also shows a regulatory effect on the V5+ /V4+ redox process due to the reducing functional group on pAP. The novel composite electrode with porous structure exhibits outstanding reversible specific capacity (386.7 mAh g-1 , 0.1 A g-1 ) at a high load of 6.5 mg cm-2 , and superior capacity retention of 80% at 3 A g-1 for 2100 cycles.

4.
Adv Sci (Weinh) ; 10(36): e2306656, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38041501

RESUMO

The practical application of AZIBs is hindered by problems such as dendrites and hydrogen evolution reactions caused by the thermodynamic instability of Zinc (Zn) metal. Modification of the Zn surface through interface engineering can effectively solve the above problems. Here, sulfonate-derivatized graphene-boronene nanosheets (G&B-S) composite interfacial layer is prepared to modulate the Zn plating/stripping and mitigates the side reactions with electrolyte through a simple and green electroplating method. Thanks to the electronegativity of the sulfonate groups, the G&B-S interface promotes a dendrite-free deposition behavior through a fast desolvation process and a uniform interfacial electric field mitigating the tip effect. Theoretical calculations and QCM-D experiments confirmed the fast dynamic mechanism and excellent mechanical properties of the G&B-S interfacial layer. By coupling the dynamics-mechanics action, the G&B-S@Zn symmetric battery is cycled for a long-term of 1900 h at a high current density of 5 mA cm-2 , with a low overpotential of ≈30 mV. Furthermore, when coupled with the LMO cathode, the LMO//G&B-S@Zn cell also exhibits excellent performance, indicating the durability of the G&B-S@Zn anode. Accordingly, this novel multifunctional interfacial layer offers a promising approach to significantly enhance the electrochemical performance of AZIBs.

5.
Sci Bull (Beijing) ; 68(19): 2170-2179, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37633831

RESUMO

Aqueous Zn2+ ion batteries present notable advantages, including high abundance, low toxicity, and intrinsic nonflammability. However, they exhibit severe irreversibility due to uncontrolled dendrite growth and corrosion reactions, which limit their practical applications. Inspired by their distinct molecular recognition characteristics, supramolecular crown ethers featuring interior cavity sizes identical to the diameter of Zn2+ ions were screened as macrocyclic hosts to optimize the Zn2+ coordination environment, facilitating the suppression of the reactivity of H2O molecules and inducing the in-situ formation of organic-inorganic hybrid dual-protective interphase. The in-situ assembled interphase confers the system with an "ion-sieving" effect to repel H2O molecules and facilitate rapid Zn2+ transport, enabling the suppression of side reactions and uniform deposition of Zn2+ ions. Consequently, we were able to achieve dendrite-free Zn2+ plating/stripping at 98.4% Coulombic efficiency for approximately 300 cycles in Zn||Cu cell, steady charge-discharge for 1360 h in Zn||Zn symmetric cell, and improved cyclability of 70% retention for 200 cycles in Zn||LMO full cell, outlining a promising strategy to challenge lithium-ion batteries in low-cost, and large-scale applications.

6.
Sensors (Basel) ; 23(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37447843

RESUMO

Western corn rootworm (WCR) is one of the most devastating corn rootworm species in North America because of its ability to cause severe production loss and grain quality damage. To control the loss, it is important to identify the infection of WCR at an early stage. Because the root system is the earliest feeding source of the WCR at the larvae stage, assessing the direct damage in the root system is crucial to achieving early detection. Most of the current methods still necessitate uprooting the entire plant, which could cause permanent destruction and a loss of the original root's structural information. To measure the root damages caused by WCR non-destructively, this study utilized MISIRoot, a minimally invasive and in situ automatic plant root phenotyping robot to collect not only high-resolution images but also 3D positions of the roots without uprooting. To identify roots in the images and to study how the damages were distributed in different types of roots, a deep convolution neural network model was trained to differentiate the relatively thick and thin roots. In addition, a color camera was used to capture the above-ground morphological features, such as the leaf color, plant height, and side-view leaf area. To check if the plant shoot had any visible symptoms in the inoculated group compared to the control group, several vegetation indices were calculated based on the RGB color. Additionally, the shoot morphological features were fed into a PLS-DA model to differentiate the two groups. Results showed that none of the above-ground features or models output a statistically significant difference between the two groups at the 95% confidence level. On the contrary, many of the root structural features measured using MISIRoot could successfully differentiate the two groups with the smallest t-test p-value of 1.5791 × 10-6. The promising outcomes were solid proof of the effectiveness of MISIRoot as a potential solution for identifying WCR infestations before the plant shoot showed significant symptoms.


Assuntos
Besouros , Robótica , Animais , Zea mays , Raízes de Plantas/química , Larva
7.
J Mater Chem B ; 10(47): 9906-9913, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36448473

RESUMO

Realizing rapid and stable bonding under humid conditions has remained a challenge in adhesion science and wound dressing. In this study, polyacrylate-based underwater tape with water-enhanced adhesion and antimicrobial performance was designed and synthesized. Good underwater adhesion performance is achieved through the reasonable selection of comonomers, among which 4-hydroxybutyl acrylate (4-HBA) and isobornyl acrylate (IBOA) provide rich hydrogen bond interactions and a rigid side chain stable structure, respectively. The former effectively increases the interface strength between the tape and the substrate, while the latter ensures that the tape can maintain a good cohesion strength under water. Besides, povidone iodine (PVP-I2) as a reinforcing filler and germicidal factor endows the tape with tunable mechanical properties and impressive antimicrobial abilities. This work provides a facile approach to prepare a wet adhesive for medical and industrial fields which can be used as wound dressing and underwater adhesive materials.


Assuntos
Anti-Infecciosos , Povidona-Iodo , Povidona-Iodo/farmacologia
8.
Angew Chem Int Ed Engl ; 61(49): e202212231, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36239266

RESUMO

Due to the excellent specific capacity and high working voltage, manganese oxide (MnO2 ) has attracted considerable attention for aqueous zinc-ion batteries (AZIBs). However, the irreversible structural collapse and sluggish ionic diffusion lead to poor rate capability and inferior lifespan. Herein, we proposed a novel organic/inorganic hybrid cathode of carbon-based poly(4,4'-oxybisbenzenamine)/MnO2 (denoted as C@PODA/MnO2 ) for AZIBs. Various in/ex situ analyses and theoretical calculations prove that PODA chains with C=N groups can provide a more active surface/interface for ion/electron mobility and zinc ion storage in the hybrid cathode. More importantly, newly formed Mn-N interfacial bonds can effectively promote ion diffusion and prevent Mn atoms dissolution, enhancing redox kinetics and structural integrity of MnO2 . Accordingly, C@PODA/MnO2 cathode exhibits high capacity (321 mAh g-1 or 1.7 mAh cm-2 at 0.1 A g-1 ), superior rate performance (88 mAh g-1 at 10 A g-1 ) and excellent cycling stability over 2000 cycles. Hence, rational interfacial designs shed light on the development of organic/inorganic cathodes for advanced AZIBs.

9.
Sensors (Basel) ; 22(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36146406

RESUMO

The electric bicycle-sharing system (EBSS) is the fourth-generation urban shared bicycle travel system, which effectively improves the travel efficiency of urban residents and solve the problem of urban congestion. This study attempts to use an extended technology acceptance model (TAM) method to study the acceptance of EBSSs. We had introduced four potential variables, including perceived pleasure (PP), perceived environmental value (PEV), perceived cost (PC), and perceived reliability (PR), into the classic TAM to form a new EBSS-TAM. Data were obtained by using a Likert scale questionnaire from 399 citizens in China. Partial least-squares structural equation modeling (PLS-SEM) with reflective constructs was employed as the analysis method. The results showed that: (1) the EBSS-TAM can explain user behaviors regarding the use of EBSSs. PP has a positive impact on behavior attitude (BA) while having no impact on behavior intention (BI). PEV has no impact on BA and BI. PC has a negative impact on BA and has no impact on BI. PR has a positive impact on BA while having no impact on BI. Perceived ease of use (PEU) has a positive impact on PP and PEV. (2) Younger users (under 35 years old) are more likely to change from liking CBSSs to using EBSSs than older users are. Male users are more satisfied with EBSSs because of their ease of use. The users who never used CBSSs are more likely to perceive the environmental protection value of EBSSs. Some managerial implications were proposed for the EBSSs.


Assuntos
Ciclismo , Intenção , Adulto , Atitude , Humanos , Análise de Classes Latentes , Masculino , Reprodutibilidade dos Testes
10.
Sensors (Basel) ; 20(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32629882

RESUMO

High-throughput imaging technologies have been developing rapidly for agricultural plant phenotyping purposes. With most of the current crop plant image processing algorithms, the plant canopy pixels are segmented from the images, and the averaged spectrum across the whole canopy is calculated in order to predict the plant's physiological features. However, the nutrients and stress levels vary significantly across the canopy. For example, it is common to have several times of difference among Soil Plant Analysis Development (SPAD) chlorophyll meter readings of chlorophyll content at different positions on the same leaf. The current plant image processing algorithms cannot provide satisfactory plant measurement quality, as the averaged color cannot characterize the different leaf parts. Meanwhile, the nutrients and stress distribution patterns contain unique features which might provide valuable signals for phenotyping. There is great potential to develop a finer level of image processing algorithm which analyzes the nutrients and stress distributions across the leaf for improved quality of phenotyping measurements. In this paper, a new leaf image processing algorithm based on Random Forest and leaf region rescaling was developed in order to analyze the distribution patterns on the corn leaf. The normalized difference vegetation index (NDVI) was used as an example to demonstrate the improvements of the new algorithm in differentiating between different nitrogen stress levels. With the Random Forest method integrated into the algorithm, the distribution patterns along the corn leaf's mid-rib direction were successfully modeled and utilized for improved phenotyping quality. The algorithm was tested in a field corn plant phenotyping assay with different genotypes and nitrogen treatments. Compared with the traditional image processing algorithms which average the NDVI (for example) throughout the whole leaf, the new algorithm more clearly differentiates the leaves from different nitrogen treatments and genotypes. We expect that, besides NDVI, the new distribution analysis algorithm could improve the quality of other plant feature measurements in similar ways.


Assuntos
Folhas de Planta , Análise Espectral , Zea mays , Algoritmos , Clorofila/análise , Nitrogênio/análise , Folhas de Planta/química
11.
Chem Biol Drug Des ; 78(4): 558-66, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21733125

RESUMO

NAD(P)H: quinone oxidoreductase1 (NQO1) is an important detoxification enzyme that can protect mammalian cells against toxic quinones and reduce the risk of tumorigenesis. In this study, it was found that salvianolic acid B (SaB), lithospermic acid (LA), and rosmarinic acid (RA), three main hydrophilic constituents in Danshen, conjugated with glutathione (GSH) easily in vitro but exhibited no NQO1-inducing activities in Hepa 1c1c7 cells, which might attribute to their poor absorptions. After a simple methylation strategy that aimed at improving the liposolubility, both the NQO1-inducing activities and the absorptions in cells of the phenolic acids improved obviously, without losing the GSH-conjugating abilities. The concentration to double the specific activity of NQ01 values of methylated products of lithospermic acid and rosmarinic acid were 17.86 ± 2.34 µg/mL and 11.97 ± 0.60 µg/mL, respectively. The findings indicated that methylation is an effective strategy to improve the NQO1-inducing activities of phenolic acids in Danshen.


Assuntos
Benzofuranos/farmacologia , Cinamatos/farmacologia , Depsídeos/farmacologia , NAD(P)H Desidrogenase (Quinona)/metabolismo , Salvia miltiorrhiza/química , Animais , Benzofuranos/química , Linhagem Celular Tumoral , Cinamatos/química , Depsídeos/química , Glutationa/química , Glutationa/farmacologia , Hidroxibenzoatos/química , Hidroxibenzoatos/farmacologia , Metilação , Camundongos , Ácido Rosmarínico
12.
Rapid Commun Mass Spectrom ; 23(18): 2857-66, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19670344

RESUMO

Quinone reductase (QR) induction is a reliable biomarker of phase II enzyme induction. In this study, glutathione (GSH) was employed and a liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was introduced to reveal the chemical constituents with QR activity from the ethyl acetate extract of roots Salvia miltiorrhiza ('Danshen') and nine tanshinones (9, 13, 17-19, 21, 24-26), which could conjugate with GSH, were characterized by LC/MS/MS and considered to have QR activities. Then, thirteen tanshinones, including six compounds (17, 18, 21, 24-26) of the above nine tanshinones, were isolated to conduct QR induction evaluation, and it was found that miltirone and its derivatives (18, 20, 24, 26) exhibited significant activities. The GSH conjugate abilities of the isolated tanshinones were also examined; this showed that compounds 18, 20, 24 and 26 had good conjugating abilities with GSH. Compared with the in vitro bioactivity screening results, this proved that conjugate ability is related with QR activity, so an LC/MS/MS method can be applied to find more active compounds.


Assuntos
Cromatografia Líquida/métodos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fenantrenos/química , Salvia miltiorrhiza/química , Espectrometria de Massas em Tandem/métodos , Abietanos , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Fenantrenos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
13.
J Chromatogr A ; 1216(24): 4859-67, 2009 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-19439309

RESUMO

In the present study, we examined the potential chemopreventive activity of dichloromethane extract of Eurycorymbus cavaleriei by investigating the change of constitutions after incubation with glutathione (GSH). The major constitutions in the dichloromethane extract of E. cavaleriei were cumarin compounds and their cleavage pattern was examined by LC-MS-MS and the characteristic product ions at m/z 206 and 207 were helpful to determine the substitutions of coumarinolignoid compounds. The mechanism of conjugations of 5'-demethylaquillochin and its isomer with GSH was discussed and validated through analysis of the conjugations of reference compound 6-hydroxy-7-methoxycoumarin with GSH by LC-MS-MS and NMR spectrum. The relative ability to induce the detoxification enzyme, NAD(P)H:quinone oxidoreductase 1 (NQO1) of nine coumarin compounds was tested which also showed 5'-demethylaquillochin exhibited the most potential chemopreventive ability. These observations suggest that 5'-demethylaquillochin and its isomer from the dichloromethane extract of E. cavaleriei have potential as chemopreventive agents through induction of detoxification enzymes.


Assuntos
Quimioprevenção , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Extratos Vegetais/química , Sapindaceae/química , Humanos , Cloreto de Metileno/química , Extratos Vegetais/farmacologia
14.
Rapid Commun Mass Spectrom ; 22(23): 3783-90, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18973198

RESUMO

For detection and differentiation of two types of triterpenoid saponins based on different aglycons of the lupane and oleanane skeleton from the roots of Pulsatilla chinensis (Bunge) Regel, the silver ion was introduced and electrospray ionization multi-stage tandem mass spectrometry was applied to analyze eleven triterpenoid saponin silver complexes. The quasi-molecular ion [M+Ag](+) was observed in the full-scan MS spectra of all the silver complexes. The MS(2) data of the [M+Ag](+) ion provided structural information on the sugar sequence of the oligosaccharide chains and the aglycon of the saponins. There are two patterns in the cleavage pathway of oleanane-type saponins. One is elimination of the sugar chain and subsequent loss of the carboxylic group which is the same as the cleavage of lupine-type saponins. The other is loss of the distinguishing ions at m/z 72 and 28 (C(2)H(4)) followed by loss of the carboxylic group. Diagnostic fragmentation pathways of the silver complexes of the saponins allow successful identification of the two types of saponins from the roots of Pulsatilla chinensis (Bunge) Regel.


Assuntos
Raízes de Plantas/química , Pulsatilla/química , Saponinas/química , Prata/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Cloreto de Metileno/química , Saponinas/análise , Triterpenos/análise , Triterpenos/química
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