Iraqi Journal of Natural Sciences and Nanotechnology

Green Synthesized Copper Oxide Nanoparticles Effect on Gene Expression for Biofilm Forming E. Coli

2024-04-02T02:57:45+03:00

Biofilm bacteria pose a profound threat to human and animal health. This study helps to explore the potential anti-gene expression effect of the green copper nanoparticles (CuONPs) on biofilm genes in strong biofilm forming E. coli

The anti- gene expression of green synthesis of CuONPs in different concentrations (MIC and Sub MIC) were evaluated against E. coli biofilm genes (luxS, mqsR, fliA) with housekeeping GapA gene by Real- time quantitive polymerase chain reaction (RT- qPCR) after treatment in comparative with control.

The results revealed that green CuONPs significant effective on biofilm gene expression by down regulate of luxS gene in fold change (1.2, 4.92) in human E. coli isolates and (0.744, 6.01) in animals in MIC and Sub MIC concentration respectively, with comparative control (14.870) and (12.616) respectively. The expression of Mqsr gene was down regulate after treatment with green CuONPs fold change (0.95, 9.06) and (1.078, 6.7) in human and animals in MIC and Sub MIC concentrations respectively with comparative control (13.9) and (18.8) respectively. Also, the expression of Flia gene was decrease after treatment with green CuONPs fold change (1.054, 7.06) and (0.5, 7.4) in human and animals of MIC and Sub MIC Concentration respectively with comparative control (16.318) and (20.353) respectively

Conclusion: Green CuONPs showed an excellent inhibitory effect and anti-biofilm activity against MDR biofilm E. coli genetically which act as down- regulator of biofilm genes in strong biofilm forming E.coli.

Studying ZnO:Al's Structural and Optical Characteristics by Chemical Spray Pyrolysis Method

2024-04-02T02:57:45+03:00

In this study, pure zinc oxide films doped with (Al) were prepared by spray pyrolysis technique, with percentages of (3,5 and 7%) and molar concentrations (0.05), on glass substrates at a temperature of (350 ^oC). X-ray diffraction pattern showed that pure zinc oxide films are all polycrystalline and have a hexagonal structure with a preferred growth direction (002). Using atomic force microscopy (AFM), the surface topography of the produced films was investigated. The findings that emerged from the analysis demonstrated a reduction in the membrane's surface roughness after doping as well as a reduction in particle size (126-55.64nm). Besides, the scanning electron microscopy (FE-SEM) results of all generated films were examined and reviewed in order to understand the composition of their surfaces and to determine the particle size, in order that practically all surfaces are covered with the spherical particles, which are collected longitudinally into ribbon-like structures linked to one another. On the other hand, optical properties have shown that the values of the energy gap for direct transitions increased from (3.73 eV) for pure films to (3.80 eV) for aluminum doped films. The optical properties investigation included transmittance spectrum, absorption coefficient and energy gap. The transmittance (89%) was within the visible spectrum region.

Thermal, Solid Conductivity and Antioxidant Study of New Organoselenium Compounds Based on 1,4-Bis(chloromethyl)-2,5 Dimethylbenzene

2024-04-02T02:57:45+03:00

Of new selenium organ derivatives, two types of derivatives were prepared in two or three steps. In the first one, P-xylene reacted with p-formaldehyde and hydrochloric acid gave1,4-bis(chloromethyl) -2,5-dimethylbenzene which is transformed to a selencyanide compound by reacting with KSeCN under N2 atmosphere to give the corresponding new compounds. In the second type 1,4- bis(chloromethyl) -2,5-dimethylbenzene reacted with hydroxybenzaldehyde to give (Z)-3-(4-chloro-2,5-dimethylstyryl) phenol which reacted with KSeCN under N2 atmosphere to give the corresponding new compounds. All compounds were characterized by melting point, FTIR, elemental analysis, UV- Visible, 1H-NMR and13C-NMR and Mass spctra. Meanwhile, TG/DTA analysis of some of these ligands was conducted to evaluate the thermal stability, kinetic, and characteristic thermodynamic parameters. Antioxidant study showed that the prepared compounds under study have good efficacy for capturing the free radical DPPH, close to the activity of the standard antioxidant VitC, which was used in different concentrations.

Green Synthesis Methods of Schiff Base Compounds: A Review

2024-04-02T02:57:45+03:00

Synthesis of Schiff bases using the principles of green chemistry is an environmentally friendly approach to obtain these important organic compounds. Schiff bases are widely utilized in various applications, but traditional synthesis methods often involve the use of toxic reagents and solvents. This review highlights a sustainable and ecological strategy for the preparation of the Schiff base. The green chemistry method emphasizes the selection of non-toxic and readily available starting materials, such as primary amines and carbonyl compounds, while minimizing waste generation and energy consumption. Environmentally benign solvents, like water or ethanol, are favored over toxic organic solvents. The use of green catalysts, including solid or bio-derived catalysts, enhances reaction rates and selectivity, reducing the need for excess reagents. The synthesis is conducted under mild reaction conditions, such as ambient or slightly elevated temperatures, to avoid the formation of hazardous byproducts. The work-up and purification processes are optimized to minimize waste production, employing simple techniques like filtration or recrystallization. The schiff bases that are synthesized are categorized utilizing spectroscopic techniques, such as NMR, IR, or mass spectrometry, to confirm their structures and purities. By employing green chemistry principles, the preparation of Schiff bases becomes more sustainable and environmentally conscious, contributing to the overall goal of a greener chemical synthesis. This abstract serves as an introduction to the green chemistry method for preparing Schiff bases, providing a concise overview of the approach's key principles and highlighting its potential to reduce environmental impact while obtaining high-quality organic compounds.

Structural Morphology and Optical Properties of the Activated Carbon Decorated in Rubber Type Buna- N Nanoparticles Used in Industrial Applications

2024-04-02T02:57:45+03:00

Potential uses for nanomaterials in light-emitting diodes, solar cells, polarizers, light-stable colour filters, optical sensors, optical data communication, and optical data storage have led to the rise of interest in this field. Because they mix the qualities of two or more different materials and may exhibit unique mechanical, electrical, or chemical behaviours, nanomaterials are of special interest. Comprehending and adjusting these impacts may result in hybrid gadgets built from these nanocomposites that possess enhanced optical characteristics.

In this work prepared polymer Buna-N with Activated carbon nanocomposites of well-defined compositions and studied the optical properties of powders and their thin films. The UV-visible light absorption spectrum was employed to describe the optical properties of industrial rubber – activated carbon composites. These composites, consisting of Plastic polymer Buna-N revealed a novel UV-visible absorption band in the wavelength range of 226-235 nm. This distinctive feature is attributed to interchain interactions within the material. To assess the optical properties, a successful optical transmission method was employed, enabling the determination of crucial parameters such as dielectric constant, absorption coefficient (α), and energy gap. Four samples of industrial rubber – activated carbon composites were analyzed in this manner.

The UV–Visible spectrophotometer served as the primary tool for the optical characterization. The results highlighted the strong dependence of these properties on both the material's nature and the type of radiation used.The primary objective of this research is to enhance the optical properties of the polymer Buna-N decorated with activated carbon .The aims to leverage these improved properties for the extraction of oil. The goal is to develop a material that exhibits the best-suited properties for the conditions involved in drilling and oil extraction processes.

Highly Sensitive Flexible ZnO/PET Photodetector

2024-04-02T02:57:45+03:00

Abstract:

Current study involves fabricate a photodetector based on ZnO nanorods for ultraviolet sensing application deposited onto a low cost flexible substrate of polyethylene terephthalate (PET) using chemical bath deposition (CBD) method. XRD diffraction data approved hexagonal structure (Wurtzite). Nanorod structure of Zinc Oxide were noticed utilizing field emission scanning electron microscopy with an average diameter of 150 to 225 nm. The energy bandgap of 3.27eV were obtained using UV–Vis spectroscopy measurement. The maximum responsivity value was 0.023A/W at a wavelength of 375nm. The photosensitivity (Sph), quantum efficiency (ƞ), response time, and recovery time were 1347.2, 837.53, 90.87s, and 114.57s under a UV light of 375nm at a bias voltage of 10V, respectively.

Fabrication of a Polymeric Composite Reinforced with Carbon Fibers and CuO Particles for Prosthetic Applications

2024-04-02T02:57:45+03:00

In this research, the mechanical properties (tensile strength, bending resistance, impact resistance) of samples composed of unsaturated polyester resin reinforced with carbon fibers in the form of layers, using four layers, and copper oxide at a rate of (1%, 2%, 3%, 4%) were studied. Both separately. It is used in the manufacture of prosthetic limbs. The results showed that carbon fiber reinforcement improved all mechanical properties. Where as that the tensile strength improved and reached (10.14), while the bending resistance value was (25.34), and the shock resistance also improved by a value of (1.46). However, when reinforced with copper oxide, it failed and also that the tensile strength value decreased to (4.76), and the bending resistance value also decreased to (7.47), but the impact resistance improved and its value reached (0.72).

Long-Range Hybrid Plasmonic Waveguide of Graded-Index InGaAsP Active Layer Based on InP

2024-04-02T02:57:45+03:00

A hybrid plasmonic waveguide based on indium phosphide (InP) was proposed for nanoscale optical confinement and long-range propagation at a wavelength of 1.55 µm. The waveguide consists of an InGaAsP layer designed as a ridge with a gold cap. The InGaAsP materials are suitable for InP substrates. The refractive index of In_1−xGa_xAs_yP_1−y was graded by changing the mole fraction to improve the confinement and propagation length compared with the conventional one. Changing only the y parameter with constant x results in a propagation length increase compared to the inverse case, changing only the parameter x. This parallels good results in the mode effective area ( ) and figure-of-merit (FoM) for the exact condition of changing y, expressing a good confinement condition. A propagation length of 40 µm is achieved with better confinement than the standard hybrid case. The designs proposed in this paper were simulated using COMSOL Multiphysics.

Nano-scale Investigation for Optical XOR and XNOR Logic Gates at 1.55 μm

2024-04-02T02:57:46+03:00

In this article, nano-rings Insulator-Metal-Insulator (IMI) plasmonic waveguides are used to propose, simulate, design, and construct all-optical (XOR and XNOR) logic gates. The Finite Element Method (FEM) has been used to develop and numerically simulate the proposed two-dimensional (2-D) structure of plasmonic gates. Four metrics are used to assess the performance of the proposed device: insertion loss, modulation depth (MD), transmission, and extension ratio (ER). Glass and silver were used to build the suggested building. Destructive and constructive interferences were used to create the functioning of the proposed plasmonic gates. According to numerical simulations, the proposed plasmonic gates with a transmission threshold of (0.3) could be realized in a single structure operating at1.55 μm. The characteristics of this device were as follows: medium Extension Ratio values, high MD values, transmission above 200% in a single state of XNOR gate. This technology is also considered essential to all-optical computers and opening the door to future access to nanophotonic integrated circuits.

Synthesis and Characterization of PMMA/Bi2O3:Fe2O3 Composites as Gamma Radiation Shielding

2024-04-02T02:57:46+03:00

This study investigates several mechanical properties, including hardness, as well as the radiation attenuation capacity of samples prepared from PMMA (Polymethyl Methacrylate) as the base material, along with nano-oxides comprising Nano Bismuth Trioxide (Bi₂O₃) and Nano Iron Trioxide (Fe₂O₃) at varying doping percentages (0%, 0.5%, 1%, 3%, 5%). The linear attenuation coefficient (µ), absorptivity (A), and transmittance (T) were determined using the radioactive isotopes Bismuth-207 (Bi²⁰⁷) and Cesium-137 (Cs¹³⁷).The experimental results exhibit a notable enhancement in hardness and radiation attenuation coefficients in samples as the doping percentage increases. Particularly, samples with a 5% doping ratio demonstrated the most promising outcomes. Consequently, they can be regarded as superior shielding materials suitable for radiation applications due to their increased linear attenuation coefficient values. Furthermore, absorptivity values witnessed an increment with heightened radiation effectiveness of the radioactive source and an increase in both shield thickness and doping ratio. In contrast, transmittance values declined with the augmentation of sample thickness and doping ratio.