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1.
Chem Rec ; 24(1): e202300302, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38010947

RESUMO

As supercapacitor (SC) technology continues to evolve, there is a growing need for electrode materials with high energy/power densities and cycling stability. However, research and development of electrode materials with such characteristics is essential for commercialization the SC. To meet this demand, the development of superior electrode materials has become an increasingly critical step. The electrochemical performance of SCs is greatly influenced by various factors such as the reaction mechanism, crystal structure, and kinetics of electron/ion transfer in the electrodes, which have been challenging to address using previously investigated electrode materials like carbon and metal oxides/sulfides. Recently, tellurium and telluride-based materials have garnered increasing interest in energy storage technology owing to their high electronic conductivity, favorable crystal structure, and excellent volumetric capacity. This review provides a comprehensive understanding of the fundamental properties and energy storage performance of tellurium- and Te-based materials by introducing their physicochemical properties. First, we elaborate on the significance of tellurides. Next, the charge storage mechanism of functional telluride materials and important synthesis strategies are summarized. Then, research advancements in metal and carbon-based telluride materials, as well as the effectiveness of tellurides for SCs, were analyzed by emphasizing their essential properties and extensive advantages. Finally, the remaining challenges and prospects for improving the telluride-based supercapacitive performance are outlined.

2.
Chem Rec ; 24(1): e202300235, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37753795

RESUMO

Since the initial MXenes were discovered in 2011, several MXene compositions constructed using combinations of various transition metals have been developed. MXenes are ideal candidates for different applications in energy conversion and storage, because of their unique and interesting characteristics, which included good electrical conductivity, hydrophilicity, and simplicity of large-scale synthesis. Herein, we study the current developments in two-dimensional (2D) MXene nanosheets for energy storage and conversion technologies. First, we discuss the introduction to energy storage and conversion devices. Later, we emphasized on 2D MXenes and some specific properties of MXenes. Subsequently, research advances in MXene-based electrode materials for energy storage such as supercapacitors and rechargeable batteries is summarized. We provide the relevant energy storage processes, common challenges, and potential approaches to an acceptable solution for 2D MXene-based energy storage. In addition, recent advances for MXenes used in energy conversion devices like solar cells, fuel cells and catalysis is also summarized. Finally, the future prospective of growing MXene-based energy conversion and storage are highlighted.

3.
Small ; 18(26): e2201989, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35620957

RESUMO

Rechargeable zinc-ion batteries (ZIBs) with exceptional theoretical capacity have garnered significant interest in large-scale electrochemical energy storage devices due to their low cost, abundant material, inherent safety, high specific energy, and ecofriendly nature. Metal carbides/nitrides, known as MXenes, have emerged as a large family of 2D transition metal carbides or carbonitrides with excellent properties, e.g., high electrical conductivity, large surface functional groups (e.g., F, O, and OH), low energy barriers for the diffusion of electrolyte ions with wide interlayer spaces. After a decade of effort, significant development has been achieved in the synthesis, properties, and applications of MXenes. Thus, it has opened up various exciting opportunities to construct advanced MXene-based nanostructures for ZIBs with excellent specific energy and power. Herein, this review summarizes the advances across multiple synthesis routes, related properties, morphological and structural characteristics, and chemistries of MXenes for ZIBs. The recent development of MXene-based electrodes is introduced, and electrolytes for ZIBs are elucidated in detail. MXene-based rocking chair ZIBs, strategies to enhance the performance of MXene-based cathodes, suppress the dendrites in MXene-based anodes, and MXene-based flexible ZIBs are pointed out. A rational design and modification of the MXenes as well as the production of composites with metal oxides exhibits promise in solving issues and enhancing the electrochemical performance of ZIBs. Finally, the present challenges and future prospects for MXene-based ZIBs are discussed.

4.
Sensors (Basel) ; 22(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35336248

RESUMO

An increasing number of vehicles on the roads increases the risk of accidents. In bad weather (e.g., heavy rainfall, strong winds, storms, and fog), this risk almost doubles due to bad visibility as well as road conditions. If an accident happens, especially in bad weather, it is important to inform approaching vehicles about it. Otherwise, there might be another accident, i.e., a multiple-vehicle collision (MVC). If the Emergency Operations Center (EOC) is not informed in a timely fashion about the incident, fatalities might increase because they do not receive immediate first aid. Detecting humans or animals would undoubtedly provide us with a better answer for reducing human fatalities in traffic accidents. In this research, an accident alert light and sound (AALS) system is proposed for auto accident detection and alerts with all types of vehicles. No changes are required in non-equipped vehicles (nEVs) and EVs because the system is installed on the roadside. The idea behind this research is to make smart roads (SRs) instead of equipping each vehicle with a separate system. Wireless communication is needed only when an accident is detected. This study is based on different sensors that are used to build SRs to detect accidents. Pre-saved locations are used to reduce the time needed to find the accident's location without the help of a global positioning system (GPS). Additionally, the proposed framework for the AALS also reduces the risk of MVCs.


Assuntos
Acidentes de Trânsito , Tempo (Meteorologia) , Acidentes de Trânsito/prevenção & controle , Primeiros Socorros , Sistemas de Informação Geográfica
5.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298422

RESUMO

The Internet of Things (IoT) devices generate a large amount of data over networks; therefore, the efficiency, complexity, interfaces, dynamics, robustness, and interaction need to be re-examined on a large scale. This phenomenon will lead to seamless network connectivity and the capability to provide support for the IoT. The traditional IoT is not enough to provide support. Therefore, we designed this study to provide a systematic analysis of next-generation advancements in the IoT. We propose a systematic catalog that covers the most recent advances in the traditional IoT. An overview of the IoT from the perspectives of big data, data science, and network science disciplines and also connecting technologies is given. We highlight the conceptual view of the IoT, key concepts, growth, and most recent trends. We discuss and highlight the importance and the integration of big data, data science, and network science along with key applications such as artificial intelligence, machine learning, blockchain, federated learning, etc. Finally, we discuss various challenges and issues of IoT such as architecture, integration, data provenance, and important applications such as cloud and edge computing, etc. This article will provide aid to the readers and other researchers in an understanding of the IoT's next-generation developments and tell how they apply to the real world.

6.
Sensors (Basel) ; 22(19)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36236363

RESUMO

In this paper, a secure energy trading mechanism based on blockchain technology is proposed. The proposed model deals with energy trading problems such as insecure energy trading and inefficient charging mechanisms for electric vehicles (EVs) in a vehicular energy network (VEN). EVs face two major problems: finding an optimal charging station and calculating the exact amount of energy required to reach the selected charging station. Moreover, in traditional trading approaches, centralized parties are involved in energy trading, which leads to various issues such as increased computational cost, increased computational delay, data tempering and a single point of failure. Furthermore, EVs face various energy challenges, such as imbalanced load supply and fluctuations in voltage level. Therefore, a demand-response (DR) pricing strategy enables EV users to flatten load curves and efficiently adjust electricity usage. In this work, communication between EVs and aggregators is efficiently performed through blockchain. Moreover, a branching concept is involved in the proposed system, which divides EV data into two different branches: a Fraud Chain (F-chain) and an Integrity Chain (I-chain). The proposed branching mechanism helps solve the storage problem and reduces computational time. Moreover, an attacker model is designed to check the robustness of the proposed system against double-spending and replay attacks. Security analysis of the proposed smart contract is also given in this paper. Simulation results show that the proposed work efficiently reduces the charging cost and time in a VEN.


Assuntos
Blockchain , Eletricidade , Aprendizado de Máquina
7.
Molecules ; 27(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35566017

RESUMO

In the present work, 0.25 wt%GNP-Ti composites were prepared through powder metallurgy route by adopting three types of mixing modes to investigate the extent of mixing on the mechanical and tribological properties. Dry ball milling, wet ball milling, and rotator mixing were independently employed to homogenize the composite constituents. Three types of composite powders obtained were subsequently sintered into composite pellets by cold compaction followed by vacuum sintering. Morphological investigation of composite powders performed by SEM revealed better homogenization of GNPs in Ti matrix for dry ball milled composite powder, whereas wet ball milled and rotator mixed composite powders showed aggregation and bundling of GNPs. Micro Vickers hardness of composites produced via dry ball milling is 4.56% and 15.7% higher than wet ball milled and rotator mixed samples, respectively. Wear test performed by pin-on-disk tribometer showed higher wear loss for wet ball milled and rotator mixed composites in comparison to dry ball milled.

8.
Molecules ; 27(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35956800

RESUMO

Scientific research is being compelled to develop highly efficient and cost-effective energy-storing devices such as supercapacitors (SCs). The practical use of SC devices is hindered by their low energy density and poor rate capability due to the binding agents in fabricating electrodes. Herein, we proposed flower-like highly open-structured binder-free ZnCo2O4 micro-flowers composed of nanosheets supported in nickel foam (ZnCoO@NF) with improved rate capability up to 91.8% when current varied from 2 to 20 A·g-1. The ZnCoO@NF electrode exhibited a superior specific capacitance of 1132 F·g-1 at 2 A·g-1 and revealed 99% cycling stability after 7000 cycles at a high current density of 20 A·g-1. The improved performance of the ZnCoO@NF electrode is attributed to the highly stable structure of the micro/nano-multiscale architecture, which provides both the high conduction of electrons and fast ionic transportation paths simultaneously.

9.
Molecules ; 27(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36364284

RESUMO

Zinc (Zn) ion supercapacitors (ZISCs) have attracted considerable attention as a viable energy storage technology because they are cost-effective, safe, and environmentally friendly. However, cathode materials with suitable properties are rare and need to be explored. In this regard, metal carbides (MXenes) are a good choice for capacitive energy storage, but they exhibit low capacitance. The energy storage performance of MXenes can be bossed using functionalization with heteroatom doping, e.g., nitrogen (N), to simultaneously modify ZISCs' fundamental characteristics and electrochemical properties. Herein, we present an in-situ N-functionalization of Ti3C2Tx-MXene via a hydrothermal reaction with urea (denoted as N-Ti3C2Tx-MXene). N-functionalization into Ti3C2Tx-MXene raised Ti3C2Tx-MXene's interlayer spacing and boosted the Zn-ion storage in 1 M ZnSO4 electrolyte. The N-Ti3C2Tx-MXene electrode delivered an excellent specific capacitance of 582.96 F/g at 1 A/g and retained an outstanding cycle stability of 94.62% after 5000 cycles at 10 A/g, which is 1.8 times higher than pristine Ti3C2Tx-MXene at identical conditions. Moreover, the N-Ti3C2Tx-MXene//Zn device demonstrated a maximum capacitance of 153.55 F/g at 1 A/g, retained 92% of its initial value after 5000 cycles, and its Coulombic efficiency was ~100%. This strategy considerably reduced Ti3C2Tx-MXene nanosheet restacking and aggregation and enhanced electrochemical performance. Further, this research elucidated N-Ti3C2Tx-MXene's charge-storage process and offered a fresh approach to the rational design of novel electrode materials for ZISCs.

10.
J Integr Plant Biol ; 63(11): 1856-1873, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34383388

RESUMO

Phytopathogenic fungi secrete a large arsenal of effector molecules, including proteinaceous effectors, small RNAs, phytohormones and derivatives thereof. The pathogenicity of fungal pathogens is primarily determined by these effectors that are secreted into host cells to undermine innate immunity, as well as to facilitate the acquisition of nutrients for their in planta growth and proliferation. After conventional and non-conventional secretion, fungal effectors are translocated into different subcellular compartments of the host cells to interfere with various biological processes. In extracellular spaces, apoplastic effectors cope with physical and chemical barriers to break the first line of plant defenses. Intracellular effectors target essential immune components on the plasma membrane, in the cytosol, including cytosolic organelles, and in the nucleus to suppress host immunity and reprogram host physiology, favoring pathogen colonization. In this review, we comprehensively summarize the recent advances in fungal effector biology, with a focus on the versatile virulence functions of fungal effectors in promoting pathogen infection and colonization. A perspective of future research on fungal effector biology is also discussed.


Assuntos
Fungos/metabolismo , Interações Hospedeiro-Patógeno , Doenças das Plantas , Imunidade Vegetal , Espécies Reativas de Oxigênio/metabolismo
11.
Sensors (Basel) ; 19(3)2019 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-30744097

RESUMO

Underwater Wireless Sensor Networks (UWSNs) are promising and emerging frameworks having a wide range of applications. The underwater sensor deployment is beneficial; however, some factors limit the performance of the network, i.e., less reliability, high end-to-end delay and maximum energy dissipation. The provisioning of the aforementioned factors has become a challenging task for the research community. In UWSNs, battery consumption is inevitable and has a direct impact on the performance of the network. Most of the time energy dissipates due to the creation of void holes and imbalanced network deployment. In this work, two routing protocols are proposed to avoid the void hole and extra energy dissipation problems which, due to which lifespan of the network increases. To show the efficacy of the proposed routing schemes, they are compared with the state of the art protocols. Simulation results show that the proposed schemes outperform the counterparts.

12.
J Biomol Struct Dyn ; : 1-12, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533896

RESUMO

The increasing global incidence of non-insulin-dependent diabetes mellitus (NIDDM) necessitates innovative therapeutic solutions. This study focuses on the design, synthesis and biological evaluation of Schiff base derivatives from 2-bromo-2-(2-chlorophenyl) acetic acid, particularly hydrazone compounds 4a and 4b. Both in-vitro and in-vivo assays demonstrate these derivatives' strong antidiabetic and anti-hyperlipidemic properties. In a 15-d experiment, we administered 4a and 4b at doses of 2.5 and 5 mg/kg body weight, which effectively improved symptoms of alloxan-induced diabetes in mice. These symptoms included weight loss, increased water consumption and high blood glucose levels. The compounds also normalized abnormal levels of total cholesterol (TC), triacylglycerol (TG) and low-density lipoprotein cholesterol (LDL-C), while raising the levels of high-density lipoprotein cholesterol (HDLC). Computational analysis showed that these compounds effectively inhibited the α-glucosidase enzyme by interacting with key catalytic residues, specifically Asp214 and Asp349. These computational results were confirmed through in-vitro tests, where 4a and 4b showed strong α-glucosidase inhibitory activity, with IC50 values of 0.70 ± 0.11 and 10.29 ± 0.30 µM, respectively. These compounds were more effective than the standard drug, acarbose, which had an IC50 value of 873.34 ± 1.67 µM. Mechanistic studies further indicated competitive inhibition, reinforcing the therapeutic potential of 4a and 4b for NIDDM treatment.Communicated by Ramaswamy H. Sarma.

13.
Heliyon ; 10(3): e25384, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38352791

RESUMO

Traditional herbal medicines and health supplements have been empirically used to treat various disorders but most of them are not standardized and have not been experimentally validated for safety and efficacy. In the present study, various dosage forms of traditional herbal medicines prescribed for specific diseases were collected from local practitioners at different districts of Khyber Pakhtunkhwa, Pakistan. The collected samples were analyzed for heavy metal, trace elements, and minerals using atomic absorption spectroscopy. All the tested samples contained heavy metals, trace elements and minerals in different concentrations. All the samples were tested positive for the presence of toxic heavy metals such as arsenic (As), cadmium (Cd) and lead (Pb). The trace elements like cobalt (Co), iron (Fe), zinc (Zn) and chromium (Cr) were also detected in acceptable range. Similarly, the samples analyzed were rich in some of the essential minerals such as sodium (Na), magnesium (Mg) and calcium (Ca) which are necessary for the proper functioning of the body. The hazard quotient (HQ) values were measured for toxic heavy metals to determine their safe ranges for human body. The HQ values were above the permissible range for arsenic (As) in all detected samples while for cadmium (Cd) and lead (Pb), the values ware above in 50 % of the analyzed samples. The detection of toxic metals and their HQ values beyond the permissible limits in different dosage forms raised questions about their quality. This study suggests that evaluation of traditional herbal remedies for the metals contents and their standardization are strongly recommended for quality assurance and protection of public health.

14.
J Ayub Med Coll Abbottabad ; 25(1-2): 194-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25098094

RESUMO

BACKGROUND: Globally 529,000 women die annually due to pregnancy related problems and in Pakistan alone this toll is about 35,000 deaths per annum. This situation is even more critical in the rural remote areas of Azad Jammu & Kashmir (AJK). The whole phenomenon needs a contextual assessment to ascertain the geographical, financial and socio culturaI accessibility, and availability of EmOC services in order to generate fresh evidence for the decision makers and concerned stakeholders for improving these services. METHODS: A cross-sectional study was conducted using a structured questionnaire with the women delivered in the last 15 days, whereas the geographical accessibility and availability of EmOC services were assessed by visiting EmOC facilities in the district Neelum of AJK. RESULTS: Over a hundred women delivered in the last 15 days, participated in the study. Geographically, a central EmOC facility is far away and the terrain is hilly and dangerous. Women's social status, education, husband's employment and household income were found to have a significant association with the use of EmOC services. The health facilities audit showed that around 90% centres do not have a female medical officer appointed. Moreover, the state of the equipment, medicines and the basic utilities such as water, sanitation, and electricity are not satisfactory. CONCLUSION: Accessibility of EmOC services is poor in the district Neelum. Evidence on ground calls for organisational reforms at EmOC service delivery level as well as for long term planning in other sectors for improving socioeconomic and education status of the women in Azad Jammu & Kashmir.


Assuntos
Parto Obstétrico , Serviços Médicos de Emergência , Acessibilidade aos Serviços de Saúde , Serviços de Saúde Materna , Serviços de Saúde Rural , Adulto , Estudos Transversais , Equipamentos e Provisões/provisão & distribuição , Feminino , Instalações de Saúde/normas , Humanos , Paquistão , Pobreza , Gravidez , Inquéritos e Questionários , Adulto Jovem
15.
Food Res Int ; 173(Pt 2): 113395, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803733

RESUMO

This study explored the use of millets flours as a secondary ingredient with soy protein isolate (SPI) to develop fibrous high moisture meat analogue (HMMA). Three millets (sorghum, pearl millet, and finger millet) with three incorporation levels (10%, 20%, and 30%) were extruded at 60%, 65%, and 70% moisture content. The results showed that millet type, incorporation level, and moisture content significantly influenced the system parameters and textural properties. Good visual texturization was achieved at addition of pearl millet up to 30% incorporation level and sorghum and finger millet up to 20% incorporation level. Furthermore, the textural properties of HMMA made from SPI-millet blends were compared against HMMA made from SPI-gluten blend and real chicken. The HMMA made from SPI-millet flour had lower hardness, chewiness, resilience, springiness, tensile strength, cutting strength than that for SPI and SPI-wheat gluten blend and were much closer to corresponding values for real chicken. The results also showed that each of the three millet types generated distinctly different fibre patterns (thick to thin fibres) and colour (whiter to darker) of HMMA. Thus, HMMA produced from SPI-millet flour blends can offer a wide textural, fibre pattern and colour space for different plant-based meat applications. Since millets do not have gluten, they also offer an opportunity to make gluten-free HMMA's.


Assuntos
Milhetes , Proteínas de Soja , Milhetes/química , Cor , Glutens , Carne , Grão Comestível
16.
ACS Omega ; 8(17): 15193-15202, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37151503

RESUMO

Natural materials are gaining interest as coating feedstock because their "quality to cost" ratio is better and they are more environmentally friendly than most of the synthetic ceramics. They give sufficient protection to metal surfaces against harsh conditions such as corrosion, wear, and high temperature. In the current study, chromite mineral was beneficiated and reduced to two different sizes to be used as feedstock material for thermal spray coating. Powders were upgraded by gravity and magnetic separation, respectively, and thermally sprayed onto mild steel samples by using atmospheric plasma spray (APS) equipment. Morphology, structure, phases, elemental distribution of chromite powder, and coatings were studied using field emission scanning electron microscopy, X-ray diffraction, X-ray fluorescence spectroscopy, and energy-dispersive X-ray spectroscopy. Tribological properties of APS chromite coatings were investigated by using a ball-on-disk tribometer, and corrosion resistance properties were evaluated by carrying out potentiodynamic polarization testing in 3.5% NaCl solution. It is observed that the coating has better wear and corrosion resistance and is worn by abrasive wear that includes scratching and particles pull out. Coating efficiency, surface morphology, and microhardness of the coating developed by fine powder were better than those of coarse powder coating.

17.
Chemosphere ; 313: 137421, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455663

RESUMO

Manganese (Mn)-based oxides are considered suitable positive electrode materials for supercapacitors (SCs). However, their cycle stability and specific capacitance are significantly hindered by key restrictions such as structural instability and low conductivity. Herein, we demonstrated a novel nanorod (NR)-shaped heterostructured manganese dioxide/manganese selenide membrane (MnO2/MnSe) on carbon cloth (CC) (denoted as MnO2/MnSe-NR@CC) with a high aspect ratio by a straightforward and facile hydrothermal process. Experiments have demonstrated that doping selenium atoms to oxygen sites reduce electronegativity, increasing the intrinsic electronic conductivity of MnO2, decreasing electrostatic interactions with electrolyte ions, and thus boosting the reaction kinetics. Further, the selenium doping results in an amorphous surface with extensive oxygen defects, which contributed to the emergence of additional charge storage sites with pseudocapacitive characteristics. As expected, novel heterostructured MnO2/MnSe-NR@CC as an electrode for SC exhibits a high capacitance of 740.63 F/g at a current density of 1.5 A/g, with excellent cycling performance (93% capacitance retention after 5000 cycles). The MnO2/MnSe-NR@CC exhibited outstanding charge storage capability, dominating capacitive charge storage (84.6% capacitive at 6 mV/s). To examine the practical applications of MnO2/MnSe-NR@CC-ASC as a positive electrode, MnO2/MnSe-NR@CC//AC device was fabricated. The MnO2/MnSe-NR@CC//AC-ASC device performed exceptionally well, with a maximum capacitance of 166.66 F/g at 2 A/g, with a capacitance retention of 94%, after 500 GCD cycles. Additionally, it delivers an energy density of 75.06 Wh/kg at a power density of 1805.1 W/kg and maintains 55.044 Wh/kg at a maximum power density of 18,159 W/kg. This research sheds fresh information on the anionic doping method and has the potential to be applied to the synthesis of positive electrode materials for energy storage applications.

18.
Sci Rep ; 12(1): 4910, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35318417

RESUMO

Terpenoids from natural plant sources are valuable for their diverse biological activities that have important roles in the medical and agrochemical industries. In this study, we assessed the antioxidant, antifungal, and aphicidal activities of a mixture of spinasterol and 22,23-dihydrospinasterol from the leaves of Citrullus colocynthis. We used 1,1-diphenyl-2-picrylhydrazyl (DPPH) to assess antioxidant activity, and we measured antifungal activity using mycelium growth inhibition assays with three pathogenic fungi, Magnaporthe grisea, Rhizoctonia solani, and Phytophthora infestans. Aphicidal activity against adults of Myzus persicae was determined using in vitro and in vivo assays. Spinasterol and 22,23-dihydrospinasterol exhibited moderate antioxidant activity, even at lower concentrations: 19.98% at 0.78 µg mL-1, 31.52% at 3.0 µg mL-1, 36.61% at 12.5 µg mL-1, and 49.76% at 50 µg mL-1. Spinasterol and 22,23-dihydrospinasterol showed reasonable levels of fungicidal activity toward R. solani and M. grisea, with EC50 values of 129.5 and 206.1 µg mL-1, respectively. The positive controls boscalid and carbendazim were highly effective against all fungi except boscalid for M. grisea (EC50 = 868 µg mL-1) and carbendazim for P. infestans (EC50 = 8721 µg mL-1). Significant insecticidal activity was observed in both residual and greenhouse assays, with LC50 values of 42.46, 54.86, and 180.9 µg mL-1 and 32.71, 42.46, and 173.8 µg mL-1 at 72, 48, and 24 h, respectively. The antioxidant activity of spinasterol and 22,23-dihydrospinasterol was strongly positively correlated with their antifungal and insecticidal activity. Spinasterol and 22,23-dihydrospinasterol therefore show good antioxidant and aphicidal activity with moderate fungicidal activity, making them suitable candidates for an alternative to synthetic agents.


Assuntos
Citrullus colocynthis , Triterpenos , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Folhas de Planta , Sitosteroides , Estigmasterol/análogos & derivados , Triterpenos/farmacologia
19.
Materials (Basel) ; 15(13)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35806623

RESUMO

It is of great significance to design electrochemical energy conversion and storage materials with excellent performance to fulfill the growing energy demand. Bimetallic cobalt/nickel-based electrode materials exhibit excellent electrical conductivity compared to mono oxides. However, their potential as electrode materials for high-performance supercapacitors (SCs) is limited because of their poor cycling stability and high-capacity fading. This work demonstrates the synthesis of binder-free bimetallic NiCo2O4 nano-needles supported on CC (NCO@CC) via a facile and scalable hydrothermal process. Excellent electrical conductivity and interconnected nanostructure of NCO@CC nano-needles provide the fast transfer of electrons with numerous channels for ion diffusion. Owing to such features, the binder-free NCO@CC electrode for SC discloses excellent specific capacitance (1476 Fg-1 at 1.5 Ag-1) with 94.25% capacitance retention even after 5000 cycles. From these outstanding electrochemical performances, it can be inferred that NCO@CC nano-needle array-structured electrodes may be potential candidates for SC applications.

20.
Nanomaterials (Basel) ; 12(18)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36144942

RESUMO

The interaction between cathode and anode materials is critical for developing a high-performance asymmetric supercapacitor (SC). Significant advances have been made for cathode materials, while the anode is comparatively less explored for SC applications. Herein, we proposed a high-performance binder-free anode material composed of two-dimensional ZnFe2O4 nanoflakes supported on carbon cloth (ZFO-NF@CC). The electrochemical performance of ZFO-NF@CC as an anode material for supercapacitor application was examined in a KOH solution via a three-electrode configuration. The ZFO-NF@CC electrode demonstrated a specific capacitance of 509 F g-1 at 1.5 A g-1 and was retained 94.2% after 10,000 GCD cycles. The ZFO-NF@CC electrode showed exceptional charge storage properties by attaining high pseudocapacitive-type storage. Furthermore, an asymmetric SC device was fabricated using ZFO-NF@CC as an anode and activated carbon on CC (AC@CC) as a cathode with a KOH-based aqueous electrolyte (ZFO-NF@CC||AC@CC). The ZFO-NF@CC||AC@CC yielded a high specific capacitance of 122.2 F g-1 at a current density of 2 A g-1, a high energy density of 55.044 Wh kg-1 at a power density of 1801.44 W kg-1, with a remarkable retention rate of 96.5% even after 4000 cycles was attained. Thus, our results showed that the enhanced electrochemical performance of ZFO-NF@CC used as an anode in high-performance SC applications can open new research directions for replacing carbon-based anode materials.

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