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Carica papaya, commonly known as papaya, is a fruit recognized for its substantial medicinal potential, primarily due to its wide range of bioactive compounds. This review thoroughly examines the pharmacological implications of these constituents and highlights their potential applications in drug discovery and therapy. Papaya is abundant in vitamins (A, C, and E), minerals, enzymes, and phytochemicals such as flavonoids, phenolic acids, carotenoids, and alkaloids, all of which contribute to its antioxidant, anti-aging, anti-inflammatory, and anticancer effects. The fruit demonstrates significant activity against diabetes, obesity, cardiovascular diseases, and gastrointestinal disorders. This review also discusses how environmental factors, including temperature, light, soil quality, and rainfall, impact the phytochemical composition of papaya, thereby influencing its medicinal properties. Both in vitro and in vivo studies have highlighted the therapeutic potential of papaya-derived compounds in various health conditions, including cancer, diabetes, wound healing, and cardiovascular health. Additionally, we explore papaya's role in promoting gut health and its antimicrobial properties against bacterial and viral pathogens. In conclusion, the diverse pharmacological activities of papaya's bioactive compounds position it as a valuable candidate for further research and development in drug discovery and therapeutic applications. [ABSTRACT FROM AUTHOR]

The unprecedented increase of atmospheric CO2 concentration and the associated climate change calls for the urgent implementation of CO2 mitigation approaches. Among the various proposed measures, CO2 capture from several industrial point sources or directly from air and its subsequent hydrogenation via renewable H2 towards value-added products formation has gained particular attention. Specifically, the production of CO or CH4 is of great importance for the eventual generation of liquid fuels or synthetic natural gas, respectively. Herein, an overview of the state-of-the-art noble and non-noble metal-based catalysts employed for the thermocatalytic CO2 hydrogenation towards CO (reverse water–gas shift reaction, rWGS) or CH4 (Sabatier reaction) is elaborated. A brief description of fundamental considerations is initially provided for each reaction, involving thermodynamic, mechanistic and kinetics considerations. Then, the recent catalytic studies on rWGS and Sabatier reactions over both noble metal and non-noble metal catalysts (e.g., metal oxides, carbides, metal organic frameworks) are discussed from the perspective of structure–property relationships. Lastly, the most important conclusions arising from the comparative analysis of the most promising catalysts are summarized and are complemented with proposed outlooks associated with future directions towards the rational design of highly active and selective catalytic materials for each process. Highlights: Recent advances on the catalytic CO2 hydrogenation to CO or CH4 Comprehensive overview and comparison of state-of-the-art catalytic systems Thermodynamic, mechanistic and kinetics considerations Rational design of cost-efficient and highly active CO2 hydrogenation catalysts [ABSTRACT FROM AUTHOR]

Seeds, as the initial products in agricultural systems, play a pivotal role in ensuring quality, fundamental to national food security and sustainable agricultural development. This study introduces a concept integrating public governance and evolutionary game theory to construct a quadripartite evolutionary game model involving seed companies, certification agencies, farmers, and governmental departments. It considers the strategic choices of these stakeholders under varying economic motivations and market mechanisms, as well as the influence of external regulation and incentives on game strategies. The existence conditions for evolutionarily stable strategy combinations are determined using the Lyapunov first method, and MATLAB is employed for numerical simulation analysis to validate the game analysis under initial conditions. The simulation results reveal two potential equilibrium points corresponding to different strategic choices among stakeholders. The study finds that producing high-quality seeds and the refusal of certification agencies to engage in rent-seeking are crucial for ensuring seed quality. Additionally, the cost–benefit ratio of seed companies, the speculative cost of certification agencies, and the rights-protection cost of farmers are key determinants in the evolution of seed quality assurance strategies. This research also holds practical significance in enhancing seed quality assurance mechanisms and fostering sustainable development in agriculture. [ABSTRACT FROM AUTHOR]

Aiming at the problem of coal gangue identification in the current fully mechanized mining face and coal washing, this article proposed a convolution neural network (CNN) coal and rock identification method based on hyperspectral data. First, coal and rock spectrum data were collected by a near-infrared spectrometer, and then four methods were used to filter 120 sets of collected data: first-order differential (FD), second-order differential (SD), standard normal variable transformation (SNV), and multi-style smoothing. The coal and rock reflectance spectrum data were pre-processed to enhance the intensity of spectral reflectance and absorption characteristics, as well as effectively remove the spectral curve noise generated by instrument performance and environmental factors. A CNN model was constructed, and its advantages and disadvantages were judged based on the accuracy of the three parameter combinations (i.e., the learning rate, the number of feature extraction layers, and the dropout rate) to generate the best CNN classifier for the hyperspectral data for rock recognition. The experiments show that the recognition accuracy of the one-dimensional CNN model proposed in this paper reaches 94.6%. Verification of the advantages and effectiveness of the method were proposed in this article. [ABSTRACT FROM AUTHOR]

A molybdenum disulfide/graphene (MoS2/G) interlayer was prepared by a simple coating method. In the interlayer, the edge of MoS2 has insufficient molybdenum–sulfur bonding coordination and has adjustable active sites. These sites can effectively limit the transfer of polysulfides by chemisorption. Meanwhile, graphene has excellent electrical conductivity and extremely large specific surface area making it a promising candidate for modifying electrodes in lithium–sulfur battery. The MoS2/G composite is used as an interlayer for a carbon nanotubes/sulfur (CNTs/S) cathode. A lithium–sulfur battery fabricated from MoS2/G interlayer delivers a high discharge capacity of 1537.2 mAh g−1 at 0.1 C. In addition, the discharge of the carbon nanotubes/sulfur@MoS2/G (CNTs/S@MoS2/G) can also remain 984.9 mAh g−1 after 450 cycles with a lower capacity decay of 0.061% per cycle at 0.5 C, exhibiting a fantastic rate performance. The CNTs/S@MoS2/G cathode shows excellent electrochemical performance, which provides a promising strategy for the developing of highly stable and commercial lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

The presence and detection of hazardous environmental gases at deficient concentrations are essential to protect human beings from intensive gas exposures. Therefore, the development of high-response gas sensors is vital to overcome these overwhelming issues. The spherical In2O3 nanoparticles are successfully decorated onto ZnO nanosheets in ZnO@In2O3 (ZIO) nanocomposites via a simple co-precipitation method. The as-prepared nanocomposites are exposed to gas-sensing applications. The fabricated gas sensors exhibit high sensing response and selectivity towards NO2 gas than other gases, tested at various working temperatures and different range of gas concentrations. The gas-sensing property of ZnO nanosheets and ZIO nanocomposites has been investigated, which reveals that 10 wt% ZIO nanocomposites shows the outstanding response of 68 at 70 ppm (1.88% higher than pristine ZnO NSs), possesses fast response/recovery time (43, 65 s) respectively, and demonstrates excellent stability and repeatability. A plausible nanostructure formation and gas-sensing mechanism are also discussed in detail. The fabricated sensors are considered potential applicants in the development of the NO2-based gas sensor industry. [ABSTRACT FROM AUTHOR]

Highlights: Operations of metal oxide semiconductors gas sensors at room temperature under photoactivation are discussed. Emerging two-dimensional (2D) materials-based gas sensors under light illumination are summarized. The advantages and limitations of metal oxides and 2D-materials-based sensors in gas sensing at room temperature under photoactivation are highlighted.Room-temperature gas sensors have aroused great attention in current gas sensor technology because of deemed demand of cheap, low power consumption and portable sensors for rapidly growing Internet of things applications. As an important approach, light illumination has been exploited for room-temperature operation with improving gas sensor’s attributes including sensitivity, speed and selectivity. This review provides an overview of the utilization of photoactivated nanomaterials in gas sensing field. First, recent advances in gas sensing of some exciting different nanostructures and hybrids of metal oxide semiconductors under light illumination are highlighted. Later, excellent gas sensing performance of emerging two-dimensional materials-based sensors under light illumination is discussed in details with proposed gas sensing mechanism. Originated impressive features from the interaction of photons with sensing materials are elucidated in the context of modulating sensing characteristics. Finally, the review concludes with key and constructive insights into current and future perspectives in the light-activated nanomaterials for optoelectronic gas sensor applications. [ABSTRACT FROM AUTHOR]

In this work, uniform rose-like MoS2 hierarchitectures have been succefully synthesized on a large scale through a template-free hydrothermal method by the reaction of hexaammonium heptamolybdate tetrahydrate [(NH4)6Mo7O24·4H2O] and thioacetamide (CH3CSNH2). The rose-like MoS2 hierarchitectures have a diameter of 350-450 nm and are formed by the assembly of numerous nanosheets. A reasonable growth mechanism of the MoS2 hierarchitectures was proposed according to the time-dependent experiments. In addition, the as-prepared rose-like MoS2 hierarchitectures show a large specific surface area of 33.72 m2 g−1 with a dominant pore diameter of 46 nm. UV-Vis absorption spectrum indicated that the sample shows a large blue-shift compared to bulk MoS2. The photocatalytic properties were investigated and exhibit enhanced visible light photocatalytic performance with the assistence of H2O2, which can be attributed to the special structural feature with an open and porous nanostructured surface layer that significantly facilitates the diffusion and mass transportation of MB molecules and oxygen species in photochemical reaction of MB degradation. This resulting rose-like MoS2 hierarchitectures are very promising visible light photocatalysts for the degradation of dye pollutants and other applications. [ABSTRACT FROM AUTHOR]

The search for high capacity, low-cost electrode materials for lithium-ion batteries is a significant challenge in energy research. Among the numerous potential candidates, layered compounds such as MoS2 (Molybdenum Disulfide) have attracted increasing attention. A facile hydrothermal reduction process using hexadecyltrimethy ammonium bromide (CTAB) as surfactant was developed for the synthesis of lithium-ion battery anode material MoS2 nanoflowers. The impact of CTAB on morphology and electrochemical performance of MoS2 has been investigated. With the increase of CTAB content, MoS2 ultrathin nanosheets with high specific surface area and more active sites have been successfully synthesized. Electrochemical measurements demonstrated that MoS2 nanoflowers synthesized with 1% content of CTAB have better electrochemical performance than others as anode materials for Li-ion batteries, which yield a high discharge capacity of 1245 mAh g−1 at a current density of 50 mA g−1 and a stable capacity retention of 740 mAh g−1 until 100 electrochemical cycles. [ABSTRACT FROM AUTHOR]

High performance microwave absorber consisting of Fe@Ni nanoparticles (NPs) modified reduced graphene oxide (RGO) and epoxy resin was successfully prepared. Fe@Ni NPs obtained via electroless plating method could be simply anchored on the surface of RGO sheets because of its high surface area, as well as residual organic groups of RGO. The crystal/micro-structure and magnetic properties of as-synthesized samples were subsequently analyzed by XRD, SEM, TEM, XPS and VSM, while electromagnetic properties were tested by vector network analyzer. The synergistic effect between graphene and Fe@Ni NPs generated suitable impedance match and strong microwave attenuation ability which lead to excellent microwave absorption property. The optimal reflection loss (RL) calculated from measured electromagnetic parameters can reach up to − 22.7 dB at 14.9 GHz with a layer thickness of 2 mm. Moreover, RL values < − 10 dB is found to be 5.5 GHz within 12.5–18 GHz, almost covering the entire Ku band. It’s convincing that the as-synthesized composites are potential candidates for high-performance lightweight microwave absorbers. [ABSTRACT FROM AUTHOR]

As a new member of the transition metal dichalcogenides (TMDs) family, rhenium disulfide (ReS) is attracting more and more attention because of its many distinctive characteristics, such as extremely weak interlayer coupling and anisotropic electronic, optical, and mechanical properties. The studies on synthesis method and electrochemical properties of ReS are still rare. For the first time, three-dimensional (3D) chrysanthemum-like microspheres composed of curly ReS nanosheets have been synthesized through a facile hydrothermal method. The high-resolution TEM image indicates that the ReS nanosheet is highly crystalline with a thickness of few monolayers. As anode for lithium-ion battery, the as-synthesized 3D chrysanthemum-like ReS (C-ReS) microspheres deliver a large initial discharge capacity of 843.0 mAh g and remain 421.1 mAh g after 30 cycles. These values are much higher than that of commercial ReS. The significant enhancement in electrochemical performance can be attributed to its porous and chrysanthemum-like microsphere structure constructed by few-layered curly ReS nanosheets. This unique architecture can allow for easy electrolyte infiltration, efficient electron transfer, and ionic diffusion. The facile synthesis approach can be extended to synthesize other two-dimensional TMDs semiconductors. The study renders ReS a promising future in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

There is a growing interest in herbal teas due to their health promoting properties. In this study, chemical composition, antioxidant activity and consumer acceptance of Buddleja saligna herbal teas were determined. Protein (14 g/ 100 g) and carbohydrate (85 g/ 100 g) were the major nutrients in fresh leaves and processed green, oolong and black teas. Ash, crude fiber and lipids were very low in all samples. Fe contents of oolong and black (28 mg/100 g) were almost twice that of fresh leaves. Green tea infusions showed the highest total phenolic contents (5 GAE g/ml), which were twice those of oolong and black teas. By DDPH (2,2-diphenyl-1-picrylhydrazyl) assay, black tea infusion exhibited a slightly high radical scavenging activity (81.5 % ± 3.8) compared to green tea (78.6 ± 3.7) and oolong (78.4 ± 2.8). Oolong tea and black teas were the most liked for their taste and mouth feel compared to green tea. [ABSTRACT FROM AUTHOR]

Tea is a popular daily beverage worldwide. Modulation and modifications of its basic components like catechins, alkaloids, proteins and carbohydrate during fermentation or extraction process changes organoleptic, gustatory and medicinal properties of tea. Through these processes increase or decrease in yield of desired components are evident. Considering the varied impacts of parameters in tea production, storage and processes that affect the yield, extraction of tea biomolecules at optimized condition is thought to be challenging. Implementation of technological advancements in green chemistry approaches can minimize the deviation retaining maximum qualitative properties in environment friendly way. Existed extraction processes with optimization parameters of tea have been discussed in this paper including its prospects and limitations. This exhaustive review of various extraction parameters, decaffeination process of tea and large scale cost effective isolation of tea components with aid of modern technology can assist people to choose extraction condition of tea according to necessity. [ABSTRACT FROM AUTHOR]

Highlights: Operations of metal oxide semiconductors gas sensors at room temperature under photoactivation are discussed. Emerging two-dimensional (2D) materials-based gas sensors under light illumination are summarized. The advantages and limitations of metal oxides and 2D-materials-based sensors in gas sensing at room temperature under photoactivation are highlighted. Room-temperature gas sensors have aroused great attention in current gas sensor technology because of deemed demand of cheap, low power consumption and portable sensors for rapidly growing Internet of things applications. As an important approach, light illumination has been exploited for room-temperature operation with improving gas sensor's attributes including sensitivity, speed and selectivity. This review provides an overview of the utilization of photoactivated nanomaterials in gas sensing field. First, recent advances in gas sensing of some exciting different nanostructures and hybrids of metal oxide semiconductors under light illumination are highlighted. Later, excellent gas sensing performance of emerging two-dimensional materials-based sensors under light illumination is discussed in details with proposed gas sensing mechanism. Originated impressive features from the interaction of photons with sensing materials are elucidated in the context of modulating sensing characteristics. Finally, the review concludes with key and constructive insights into current and future perspectives in the light-activated nanomaterials for optoelectronic gas sensor applications. [ABSTRACT FROM AUTHOR]