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This study investigates a prospective and straightforward method for producing graphene material derived from biomass, examining the influence of plant cell composition and functions. The experimental outcomes highlight ultrasound's crucial role in synthesizing graphene material sourced from biomass. Ultrasound, a pivotal element in the experiment, significantly affects graphene production from biomass by working synergistically with the liquid components in the solvent system. Notably, the ethanol content reduces the solution’s surface tension, facilitating the effective dispersion of biochar and graphene oxide sheets throughout the process. Simultaneously, the water content maintains the solution’s polarity, enhancing the cavitation effect induced by ultrasound. Biomass-derived graphene is exfoliated utilizing an ultrasonic bath system (134.4 W, 40 kHz, 0.5 W/cm2) from biochar. The as-synthesized graphene oxide exhibits a structure comprising a few layers while remaining intact, featuring abundant functional groups. Interestingly, the resulting product displays nanopores with an approximate diameter of 100 nm. These nanopores are attributed to preserving specific cell structures, particularly those with specialized cell wall structures or secondary metabolite deposits from biomass resources. The study's findings shed light on the impact of cellular structure on synthesizing graphene material sourced from biomass, emphasizing the potential application of ultrasound as a promising approach in graphene production.

In this study, ultrasonically driven biosynthesis of zinc oxide nanoparticles (ZnO NPs) using Swietenia macrophylla seed ethyl acetate fraction (SMEAF) has been reported. X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) analyses confirmed the presence of a pure hexagonal wurtzite structure of ZnO. Field emission scanning electron microscope images revealed the formation of uniquely identifiable uniform rice-shaped biologically synthesized ZnOSMEAF particles. The particle sizes of the biosynthesized NPs ranged from 262 to 311 nm. The underlying mechanisms for the biosynthesis of ZnOSMEAF under ultrasound have been proposed based on FTIR and XRD results. The anticancer activity of the as-prepared ZnOSMEAF was investigated against HCT-116 human colon cancer cell lines via methyl thiazolyl tetrazolium assay. ZnOSMEAF exhibited significant anticancer activity against colon cancer cells with higher potency than ZnO particles prepared using the chemical method and SMEAF alone. Exposure of HCT-116 colon cancer cells to ZnOSMEAF promoted a remarkable reduction in cell viability in all the tested concentrations. This study suggests that green sonochemically induced ZnO NPs using medicinal plant extract could be a potential anticancer agent for biomedical applications.

Heavy Pb pollution has been noted in many developed countries. This study examined Pb pollution in Jiaozhou Bay for human security. We used the survey data on the Jiaozhou Bay waters of May, September and October 1994, the results examines Pb content and its horizontal distribution in the surface water bodies, which showed that the in the waters of Jiaozhou Bay Pb content expresses the range of 0.12-2.48 μg/L, agreeing with the seawater standards of Class I and II. Moreover, it has been noted that by the view of Pb content, Pb content in May, September and October polluted the Jiaozhou Bay water bodies softly. In May, September and October, the Pb content in the waters of Jiaozhou Bay ranged from 0.12 to 1μg/L, 0.84 to 1.34 μg/L, and 0.92 to 2.48 μg/L. These results show that Pb content in May did not pollute the Jiaozhou Bay water bodies. While Pb content during September and October slightly polluted. Three sources transported mainly Pb content into Jiaozhou bay. These sources are rivers, land surface runoff and offshore ocean currents. The rivers transported the Pb content 0.47-2.48 μg/L, the land surface runoff 2μg/L and the offshore ocean currents 1.34 μg/L. It demonstrates that Pb slightly polluted rivers, land surface runoff and offshore ocean currents in the transportation of Pb. From May to October, rivers transported Pb content which varied significantly. In September, land surface runoff transported Pb content during the rainy season. In addition, the offshore currents also transported Pb content to the waters of Jiaozhou Bay. Human activities discharged Pb content to land and transported it to the ocean, relying on the land surface runoff and rivers. Thus, two channels were transporting Pb content on land to the ocean, increasing Pb content. Through ocean currents, Pb content was transported from the high-content water area to the low-content water area. Therefore, the Pb content transported by rivers and land surface runoff could raise concerns from humans.

Hg pollutes the environment, living organisms, and humans; hence, studying Hg content is essential for human health security. Using the dataset in May, September, and October, the Hg content, horizontal distribution, sources and transportation paths in the waters of Jiaozhou Bay were easily determined. These results indicate that the Hg content changing range in the waters in May, September and October was 0.015-0.150 μg/L, corresponding to the national seawater quality standards of Class I and Class II. The Hg content in the water body mainly arises from two sources, the transportation of rivers and offshore ocean currents. It from rivers' offshore ocean currents was 0.019-0.150 μg/L and 0.020 μg/L, respectively. Among them, the transportation of rivers includes the transportation of Haibo River, Licun River and Loushan River. So, a model block diagram has been built to unveil Hg contents and its different paths during the transportation to Jiaozhou Bay. Thus, it becomes easy to quantitively determine the migration process of Hg content through human activities to the ocean and rivers. Hg's different paths and contents reveal four rules for entering Jiaozhou Bay. In May, the offshore ocean currents and Haibo River did not affect by Hg pollution. In September, the Laoshan River was not polluted by it. In October, the Licun River was not, while the Haibo River exhibited light Hg pollution. When the Hg content transported by rivers was relatively low, it by offshore ocean currents became visible. From May to October, three rivers were transporting Hg content. Hg mildly polluted only one river in October, depicting that human activity is a key concern for environmental protection. It discharged by humans to land was relatively low, meanwhile only once was river transportation slightly polluted by it.

Graphene is an advanced carbon functional material with inherent unique properties that make it suitable for a wide range of applications. It can be synthesized through either the top–down approach involving delamination of graphitic materials or the bottom–up approach involving graphene assembly from smaller building units. Common top–down approaches are exfoliation and reduction while bottom–up approaches include chemical vapour deposition, epitaxial growth, and pyrolysis. A range of materials have been successfully used as precursors in various synthesis methods to derive graphene. This review analyses and discusses the suitability of conventional, plant- and animal-derived, chemical, and fossil precursors for graphene synthesis. Together with its associated technical feasibility and economic and environmental impacts, the quality of resultant graphene is critically assessed and discussed. After evaluating the parameters mentioned above, the most appropriate synthesis method for each precursor is identified. While graphite is currently the most common precursor for graphene synthesis, several other precursors have the potential to synthesize graphene of comparable, if not better, quality and yield. Thus, this review provides an overview and insights into identifying the potential of various carbon precursors for large-scale and commercial production of fit-for-purpose graphene for specific applications.