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Nanotechnology is attracting significant attention worldwide due to its applicability across various sectors. Titanium dioxide nanoparticles (TiO2NPs) are among the key nanoparticles (NPs) that have gained extensive practical use and can be synthesized through a wide range of physical, chemical, and green approaches. However, TiO2NPs have attracted a significant deal of interest due to the increasing demand for enhancing the endurance to abiotic stresses such as temperature stress. In this article, we discuss the effects of temperature stresses such as low (4 °C) and high temperatures (35 °C) on TiO2NPs. Due to climate change, low and high temperature stress impair plant growth and development. However, there are still many aspects of how plants respond to low and high temperature stress and how they influence plant growth under TiO2NPs treatments which are poorly understood. TiO2NPs can be utilized efficiently for plant growth and development, particularly under temperature stress, however the response varies according to type, size, shape, dose, exposure time, metal species, and other variables. It has been demonstrated that TiO2NPs are effective at enhancing the photosynthetic and antioxidant systems of plants under temperature stress. This analysis also identifies key knowledge gaps and possible future perspectives for the reliable application of TiO2NPs to plants under abiotic stress.
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Applications: Flow-through permeable media have a wide range of applications in biomedical engineering, geophysical fluid dynamics, and recovery and refinement of underground reservoirs and large-scale chemical applications such as filters, catalysts, and adsorbents. Therefore, this study on a nanoliquid in a permeable channel is conducted under physical constraints. Purpose and Methodology: The key purpose of this research is to introduce a new biohybrid nanofluid model (BHNFM) with (Ag-G)hybridnanoparticles with additional significant physical effects of quadratic radiation, resistive heating, and magnetic field. The flow configuration is set between the expanding/contracting channels, which has broad applications, especially in biomedical engineering. The modified BHNFM was achieved after the implementation of the bitransformative scheme, and then to obtain physical results of the model, the variational iteration method was applied. Core Findings: Based on a thorough observation of the presented results, it is determined that the biohybrid nanofluid (BHNF) is more effective than mono-nano BHNFs in controlling fluid movement. The desired fluid movement for practical purposes can be achieved by varying the wall contraction number (α1 = -0.5, -1.0, -1.5, -2.0) and with stronger magnetic effects (M = 1.0,9.0,17.0,25.0). Furthermore, increasing the number of pores on the surface of the wall causes the BHNF particles to move very slowly. The temperature of the BHNF is affected by the quadratic radiation (Rd), heating source (Q1), and temperature ratio number (θr), and this is a dependable approach to acquire a significant amount of heat. The findings of the current study can aid in a better understanding of parametric predictions in order to produce exceptional heat transfer in BHNFs and suitable parametric ranges to control fluid flow inside the working area. The model results would also be useful for individuals working in the fields of blood dynamics and biomedical engineering.
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Hydrogen is a clean and green biofuel choice for the future because it is carbon-free, non-toxic, and has high energy conversion efficiency. In exploiting hydrogen as the main energy, guidelines for implementing the hydrogen economy and roadmaps for the developments of hydrogen technology have been released by several countries. Besides, this review also unveils various hydrogen storage methods and applications of hydrogen in transportation industry. Biohydrogen productions from microbes, namely, fermentative bacteria, photosynthetic bacteria, cyanobacteria, and green microalgae, via biological metabolisms have received significant interests off late due to its sustainability and environmentally friendly potentials. Accordingly, the review is as well outlining the biohydrogen production processes by various microbes. Furthermore, several factors such as light intensity, pH, temperature and addition of supplementary nutrients to enhance the microbial biohydrogen production are highlighted at their respective optimum conditions. Despite the advantages, the amounts of biohydrogen being produced by microbes are still insufficient to be a competitive energy source in the market. In addition, several major obstacles have also directly hampered the commercialization effors of biohydrogen. Thus, this review uncovers the constraints of biohydrogen production from microbes such as microalgae and offers solutions associated with recent strategies to overcome the setbacks via genetic engineering, pretreatments of biomass, and introduction of nanoparticles as well as oxygen scavengers. The opportunities of exploiting microalgae as a suastainable source of biohydrogen production and the plausibility to produce biohydrogen from biowastes are accentuated. Lastly, this review addresses the future perspectives of biological methods to ensure the sustainability and economy viability of biohydrogen production.