Nano Zinc-Oxide Enhanced Photosynthetic Apparatus and Photosystem Efficiency of Maize (Zea Mays L.) in Sandy-Acidic Soils

Conventional Zinc (Zn) fertilization (e.g., zinc sulfate) often leads to poor availability in soils. Zinc oxide nanoparticles (nano ZnO) can be a potential solution, but their effect on crop photosynthetic activity isn’t well documented. The effects of nano ZnO (50, 100, 150, 200 mg L-1) and application methods (seed-coating, soil-drench, and foliar-spray) in comparison with ZnSO4 recommended dose were evaluated for plant height, biomass, chlorophyll pigments and photosystem efficiency in a greenhouse pot experiment. 100 mg L-1 of nano ZnO significantly increased the chlorophyll (Chl.) a, b, a+b, carotenoids (x+c), a+b/x+c, SPAD, leaf Chl., total chlorophyll content plant-1, plant height and total biological yield (by 18-30%, 33-67%, 22-38%, 14-21%, 14-27%, 12-19%, 12-23% 58-99%, 6-11% and 16-20%, respectively) and reduced Chl. a/b (by 6-22%) over the other treatments (p<0.01) irrespective of application methods. Nano ZnO applied at 100 mg L-1 significantly increased photochemical quenching (qP) and efficiency of photosystem II (EPSII) compared to 150 and 200 mg L-1 regardless of application methods. The positive correlations between Chl. a and Chl. b (r2 0.90), Chl. a+b and x+c (r2=0.71), SPAD and Chl. a (r2=0.90), SPAD and Chl. b (r2=0.94) and SPAD and Chl. a+b (r2=0.93) indicates a uniform enhancement in chlorophyll pigments; SPAD value, qP, EPSII, and growth and yield parameters. This elucidates that the application of nano ZnO at 100 mg L-1 promotes corn biochemical health and photosynthesis, irrespective of the application method. These findings have a great propounding for improving plant growth through nano ZnO bio-fortification in acidic Spodosols.

Preparation and Properties of Nano ZnO Dye Sensitized Solar Cells on (Titanium) Substrates

Nowadays, the development of science and technology has been increasing demand for energy. Energy problem has become a bottleneck to restrict the development of international social economy. People pay more and more attention to the development and research of renewable resources. Solar energy is a kind of renewable resource with great potential and no pollution. The commercialized solar cells are mainly silicon solar cells, among which the conversion efficiency of single silicon solar cells is the highest, but the cost of silicon solar cells is high. Therefore, people have been exploring new materials, among which titanium based nano ZnO dye sensitized solar cells have been paid more and more attention by scientists at home and abroad. Based on this, the preparation and performance of nano ZnO dye sensitized solar cells based on titanium are studied. In this paper, the optical anode materials of DSSC are used as the research objects. Three-dimensional ZnO nanoband, one-dimensional graded ZnO nanotube array and one-dimensional sub grade ZnO nanowire array are prepared by anodizing and hydrothermal synthesis. The photovoltaic properties of the three materials are studied. One dimensional graded ZnO, nanotube array films were prepared by two-step hydrothermal synthesis. One dimensional hierarchical ZnO nanowire array is obtained by two-step hydrothermal synthesis. The results show that DSSC is assembled by one-dimensional graded ZnO nanotube array film, and the photoelectric conversion efficiency is 5.1%. Compared with one-dimensional ZnO nanowire array, the efficiency is improved by nearly 90%. The ZnO nanowire of the sub grade is used instead of DSSC The efficiency of photoelectric conversion is only 4% in the photoanode, which is higher than that of the smooth ZnO nanowire photocell.

(Nickel) Substrate Nano-ZnO Dye-sensitized Solar Cell Preparation and Performance Research

With the rapid growth and development of the world and global economy, human material and living standards continue to improve and improve, people’s demand for renewable energy has become more and more, and many traditional energy sources, such as oil, natural gas, coal, etc., due to their limited storage capacity, serious environmental pollution during mining, and many other reasons, no longer fully meet the human demand for sustainable use of renewable energy in our era. Therefore, the development of a clean industrial energy is gradually becoming an important solution for contemporary Chinese enterprises to solve the problem of clean industrial energy utilization. Solar cells are an inexhaustible clean and green energy. It has great research and development and application value. It has attracted extensive research attention from social scientists. Among them, solar energy dye-sensitized battery solar plastic cells mainly have The dye process is simple, the cost of the preparation process is low, the conversion efficiency is high, and the large-scale production can be achieved throughout the year. Therefore, it has gradually become a hot spot in my country’s solar power battery technology research in recent years. This article aims to study the preparation and performance of (nickel) substrate nano-ZnO dye-sensitized solar cells. The optimal conditions for the synthesis of ZnO and the influence of different reaction conditions on the growth of ZnO were explored, and the growth mechanism of ZnO was speculated. The photoelectric synthesis catalytic conditions of the microspheres agglomerated between different sizes of ZnO are explored, and the direct influence of the small dye-sensitized micro-solar synthesis cells currently used in the synthesis on the synthesis of small dye-sensitized micro-solar cells is directly affected. Laboratory research results show that in order to use more reactive dyes for dye adsorption in order to improve the efficiency of the conversion using dye sensitizers and solar fuel cells, the dye film needs to pass through ZnO and be adsorbed by the dye at the same time. The morphological structure should not be too dense and the film should not be too thick; at the same time, the absorption of the dye film should be proportional to the overall coating thickness of the film. Therefore, the overall thickness of the film should be moderate when used in ZnO.

Preparation and Characterization of Chitosan–Nano-ZnO Composite Films for Preservation of Cherry Tomatoes

Chitosan is widely used as a natural preservative of fruits and vegetables, but its poor mechanical and water resistances have limited its application. Therefore, in this study, we prepared chitosan composite films by incorporating different amounts of nano-zinc oxide (nano-ZnO) to improve the mechanical properties of chitosan. We also assessed the antibacterial activity of these films against selected microorganisms. The addition of nano-ZnO improved the tensile strength (TS) and elongation at break (EAB) of the chitosan films and reduced their light transmittance. TS and EAB increased from 44.64 ± 1.49 MPa and 5.09 ± 0.38% for pure chitosan film to 46.79 ± 1.65 MPa and 12.26 ± 0.41% for a 0.6% nano-ZnO composite film, respectively. The ultraviolet light transmittance of composite films containing 0.2%, 0.4%, and 0.6% nano-ZnO at 600 nm decreased from 88.2% to 86.0%, 82.7%, and 81.8%, respectively. A disc diffusion test showed that the composite film containing 0.6% nano-ZnO had the strongest antibacterial activity against Alicyclobacillus acidoterrestris, Staphylococcus aureus, Escherichia coli, and Salmonella. In a 15-day preservation study, chitosan composite films containing 0.6% nano-ZnO maintained the soluble solid content of cherry tomatoes, effectively inhibited their respiration, and exhibited good antibacterial properties against the selected microorganisms. Overall, the prepared chitosan nano-ZnO composite film showed a good preservation effect on cherry tomatoes.

Preparation and Characterization of Photocatalytically Active Antibacterial Surfaces Covered with Acrylic Matrix Embedded Nano-ZnO and Nano-ZnO/Ag

In the context of healthcare-acquired infections, microbial cross-contamination and the spread of antibiotic resistance, additional passive measures to prevent pathogen carryover are urgently needed. Antimicrobial high-touch surfaces that kill microbes on contact or prevent their adhesion could be considered to mitigate the spread. Here, we demonstrate that photocatalytic nano-ZnO- and nano-ZnO/Ag-based antibacterial surfaces with efficacy of at least a 2.7-log reduction in Escherichia coli and Staphylococcus aureus viability in 2 h can be produced by simple measures using a commercial acrylic topcoat for wood surfaces. We characterize the surfaces taking into account cyclic wear and variable environmental conditions. The light-induced antibacterial and photocatalytic activities of the surfaces are enhanced by short-term cyclic wear, indicating their potential for prolonged effectivity in long-term use. As the produced surfaces are generally more effective at higher relative air humidity and silver-containing surfaces lost their contact-killing properties in dry conditions, it is important to critically evaluate the end-use conditions of materials and surfaces to be tested and select application-appropriate methods for their efficacy assessment.

The Effects of Silicon Dioxide Nanoparticles and Zinc Oxide Nanoparticles on Waste Land soil Bacterial and Fungal Isolates

Objective: Different bacterial and fungal isolates were collected from the wasteland municipality site, Tambaram. The antimicrobial activity of two types of nanoparticles ZnO & SiO2 [Zinc oxide and Silicon dioxide] against several types of Gram-negative bacteria and fungi was investigated in this work. Methods: P. aeruginosa, B. subtilis, Penicillium oxalicum and Aspergillus fumigatus were isolated from 5 soil samples taken from three sites of Tambaram Municipality wasteland (Chennai). After collecting the samples, we used culturing and biochemical tests to identify the microbes and then used a chemical approach to make ZnO and SiO2 nanoparticles with altered structure and morphological features. Minimum inhibitory concentration (MIC) was used to assess the antibacterial activity of these nanoparticles against various microorganisms. Results: The best inhibition zone was found in Pseudomonas sps and Bacillus sps growth at concentrations of 10 µg/ml and 5 µg /ml of nano-ZnO, respectively, whereas the lower inhibition zone was found in Penicillium oxalicum and Aspergillus fumigatus at a dosage of 2.5 µg /ml of the same nanoparticle. It was also discovered that no inhibitory zone existed in any of the bacteria and fungi at a concentration of 10 µg /ml nano-SiO2. We found that all of the bacteria and fungi we tested were completely inhibited at a concentration of 1.25 g/ml nano-ZnO (MIC), with no antibacterial activity below this concentration. When compared to data that showed that all tested bacteria were not completely inhibited even at a concentration of 0.625 g/ml of nano-SiO2. Conclusion: In comparison to the two nanoparticles (ZnO and SiO2), nano-ZnO outperformed nano-SiO2 in inhibiting most bacteria and fungi at the quantities tested in wasteland soil.