In this work, bismuth oxide nanoparticles (Bi2O3NPs) are preparation by laser ablation at diverse laser energy 200, 400, 600 and 800 mJ with 100 shots and laser wavelength 1064 nm then deposited on porous silicon (PS). X-ray diffraction (XRD) study revealed that Bi2O3NPs is crystalline and belong to α-phase with monoclinic symmetry. Atomic force microscope (AFM) study results for PS showed sponge like structure, and for Bi2O3NPs appears an average diameter of 31.09 nm coordinated in a rod-like shape, are watching and electrical properties are carried out to describe the samples. Fourier Transform Infrared (FTIR) spectra showed the oxidation of PS substrate resulting in the passivating of the surface states and for Bi2O3NPs/PS confirming the presence of Bi-O bond. The electrical properties such as barrier height (ΦB) and ideal factor (n) of the Al/PS/ Si/Al and Al/Bi2O3NPs/PS/Si/Al heterojunction were calculated from the current–voltage (I-V) measurements.

In this paper, synthesis and characterizing of bismuth oxide nanoparticles (Bi2O3NPs) are synthesized by laser ablation at different laser pulses energy 200, 400, 600 and 800 mJ with 100 shots and laser wavelength 1064 nm and porous silicon (PS) was presented. Scanning electron Microscopy (SEM), x-ray diffraction (XRD), UV–vis-NIR spectrophotometer and electrical properties are used to characterize the products. The results show X- ray patterns analysis and improve the crystalline structure of Bi2O3 nanoparticles which relate to α- phase and monoclinic symmetry. SEM image shows approximate spherical particles with a little agglomeration for both samples. From results transmittance of Bi2O3NPs suspension with energy bandgaps ranging from the infrared up to near-ultraviolet can be obtained, depending on their structure and morphology. Based on these results, we demonstrated enhanced performance of Bi2O3NPs/PS photoddetectors over a broad range of wavelengths

In this work, preparation and characterization of Bi2O3 nanoparticles (Bi2O3NPs) by laser ablation in liquid at various laser energy 200, 400, 600 and 800 mJ. X-ray diffraction (XRD) investigation is appeared broad diffraction peak when the size of the crystal becomes inside nanometer. Scanning electron Microscopy (SEM) study results for porous silicon (PS) showed sponge like structure and Bi2O3NPs nanoparticles appear as bright spots. Observed the reflectivity of Bi2O3NPs on PS is less than Si bulk and PS, however. From Raman result show peaks at 81 cm−1 and 303 cm−1 , are the specific bands of α-Bi2O3. The band at 303 cm−1 , are assumed to be because of Bi–O stretches. The electrical properties such as barrier height (ΦB) and ideality factor (n) of the Al/Bi2O3NPs/PS/Si/Al heterojunction were determined from the current–voltage (I-V) measurements. Finally, the variation of operation temperature of NO2 gas sensors which fabricated from the prepared samples on sensor sensitivity, response time and recover time have been studied, and the maximum sensitivity was about 71 % for Bi2O3NPs ablated by laser energy 600 mJ on PS.

In this work, n-type porous silicon (n-PS) was fabricated via photoelectrochemical etching (PECE) method with different etching current densities, including 5, 10, 15, 20, and 25 mA/cm2 at constant concentration of HF about 20%. The suspension mixture of standard copper oxide nanoparticles (CuO-NPs) was prepared by dissolving 0.2 g of CuO powder in 100-ml ethanol. Then, CuO-NPs were deposited on n-PS surface employing the drop-casting method. X-ray diffraction and scanning electron microscope techniques proved the cubic crystal phase with porous morphology. The current–voltage (J-V) measurements were conducted in the dark and under illumination with different intensities for n-PS and CuO/PS samples. To evaluate the photodetector-sensing performance, the responsivity (Rλ), detectivity (D), and the quantum efficiency (Q.E) tests were performed for all samples at room temperature. All results showed that the CuO-NPs on the n-PS surface lead to increase Rλ, D, and Q.E compared with n-PS-only sample.

Through the use of subband analysis, the article presents a method for selecting pauses in speech communications. An additive blending of normally distributed noise was used in the sensitivity analysis. In various noise/signal respects, the probability of making a bad decision has been identified. The findings show that the proposed sub-band method is stable when subjected to additive noise effects. 

he work out lines a method of constructing an approximate solution of a differential equation of the second order with input data obtained in the experiment (empirical functions). In such statement the problem belongs to the class of incorrect mathematical problems and often occurs, for example, in mathematical models of physical phenomena using measurement results of field experiments. To obtain the approximate solution of this problem requires construction of appropriate regularization algorithms based on the methods of the theory of functional analysis and ill-posed problems. In the present work is the construction of the approximate solution of odes with specified boundary conditions, are the socalled singular integrals. This allows you to put in the original equation Fredholm integral equation of the first kind and to find its numerical solution, i.e. the solution of the incorrect task. This uses a machine approximation of functions and their deriva- tives corresponding singular integrals and regularization method convergence of the sequence of approximate solutions, which implemented the so-called generalized inverse operators. Built in the end, a computational model allows to obtain a stable solution of illposed problems.
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1-dimensional zinc oxide (ZnO) - silver oxide (Ag2O) – silver (Ag) nanowire was prepared using a simple and inexpensive bottom-up chemical method. X-ray diffraction (XRD) results showed the presence of diffraction peaks of ZnO and Ag2O with hexagonal wurtzite phase of ZnO. Energy Dispersive X-ray (EDX) results showed the presence of energy peaks of Zinc (Zn), Silver (Ag), and Oxygen (O) elements. Filed Emission Scanning Electron Microscopy (FE-SEM) results showed that the surface morphology is nanowire (1-dimensional structure) with shapes similar to hedgehog spines and have small nanoscale diameters. The present work represents a promising step in the preparation of a 1-dimensional nanowire.

In this work, iron oxide "gamma phase" (γ-Fe2O3)-silver oxide (Ag2O) nanocomposite is prepared by a double hydrothermal method combined with Punicaceae plant extract as reducing agents. X-ray diffraction (XRD) results confirmed the presence of γ-Fe2O3 and Ag2O and delafossite silver ferrite (AgFeO2) phases. Field Emission Scanning Electron Microscopy-energy dispersive spectroscopy (FESEMEDS) results revealed nanoparticles (NPs) with a shape like a cauliflower plant. Furthermore, the anti-bacterial activity results presented high inhibition rates against Klebsiella pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Candida albicans. The present study exhibits a new approach to the preparation of metal oxides using a facile and inexpensive method