The holmium plasma induced by a 1064-nmQ-switched Nd:YAG laser in air was investigated. This work was done theoretically and experimentally.  Cowan code was used to get the emission spectra for different transition of the holmium target. In the experimental work, the evolution of the plasma was studied by acquiring spectral images at different laser pulse energies (600,650,700, 750, and 800 mJ). The repetition rates of (1Hz and 10Hz) in the UV region (200-400 nm). The results indicate that, the emission line intensities increase with increasing of the laser pulse energy and repetition rate. The strongest emission spectra appeared when the laser pulse energy is 800mJ and 10 Hz repetition rate at λ= 345.64nm, with the maximum intensi

The analytical study of optical bistability is concerned in a fully
optimized laser Fabry-Perot system. The related phenomena of
switching dynamics and optimization procedure are also included.
From the steady state of optical bistability equation can plot the
incident intensity versus the round trip phase shift (φ) for different
values of dark mistuning 
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

12
,
6
,
3
,
1.5
0 , o
   
 or finesse (F= 1, 5, 20,
100). In order to obtain different optical bistable loops. The inputoutput
characteristic for a nonlinear Fabry-Perot etalon of a different
values of finesse (F) and using different initial detuning (φ0) are used
in this rese

The seasonal behavior of the light curve for selected star SS UMI and EXDRA during outburst cycle is studied. This behavior describes maximum temperature of outburst in dwarf nova. The raw data has been mathematically modeled by fitting Gaussian function based on the full width of the half maximum and the maximum value of the Gaussian. The results of this modeling describe the value of temperature of the dwarf novae star system leading to identify the type of elements that each dwarf nova consisted of.

The distribution of the intensity of the comet Ison C/2013 is studied by taking its histogram. This distribution reveals four distinct regions that related to the background, tail, coma and nucleus. One dimensional temperature distribution fitting is achieved by using two mathematical equations that related to the coordinate of the center of the comet. The quiver plot of the gradient of the comet shows very clearly that arrows headed towards the maximum intensity of the comet.

Cold plasma is a relatively low temperature gas, so this feature enables us to use cold plasma to treat thermally sensitive materials including polymers and biologic tissues. In this research, the non-thermal plasma system is designed with diameter (3 mm, 10 mm) Argon at atmospheric pressure as well as to be suitable for use in medical and biotechnological applications.
The thermal description of this system was studied and we observed the effect of the diameter of the plasma needle on the plasma, when the plasma needle slot is increased the plasma temperature decrease, as well as the effect of the voltages applied to the temperature of the plasma, where the temperature increasing with increasing the applied voltage . Results showed t

Zinc oxide thin films were deposited by chemical spray pyrolysis onto glass substrates which are held at a temperature of 673 K. Some structural, electrical, optical and gas sensing properties of films were studied. The resistance of ZnO thin film exhibits a change of magnitude as the ambient gas is cycled from air to oxygen and nitrogen dioxide

Abstract

In this work, the plasma parameters (electron temperature (T_e), electron density( n_e), plasma frequency (f_p) and Debye length (λ_D)) have been studied by using the spectrometer that collect the spectrum of Laser produce CdTe_(X):S_(1-X) plasma at X=0.5 with different energies. The results of electron temperature for CdTe range 0.758-0.768 eV also the electron density 3.648 10¹⁸ – 4.560 10¹⁸ cm^-3  have been measured under vacuum reaching 2.5 10^-2 mbar .Optical properties of CdTe:S were determined through the optical transmission method using ultraviolet visible spectrophotometer within the r

A hand lay-up method was used to prepare Epoxy/ metal composites. Epoxy resin (EP) was used as a matrix with metal particles (Al, Cu, and Fe) as fillers.
The preparation method includes preparing square panels of composites with different weight percentage of fillers (10, 20, 30, 40, and 50%). Standard specimens (88mm in diameter) for thermal conductivity tests were prepared to measure thermal conductivity kexp.The result of experimental thermal conductivity kexp, for EP/metal composites show that, kexp increase with increasing weight percentage, For EP/ Al and EP/Cu composites, and it have have maximum values of 0.33 and 0.35 W/m.K, respectively. While kexp for EP/ Fe composite show slight increase with maximum value of 0.186 W/m.K.

Nano-structural of vanadium pentoxide (V2O5) thin films were
deposited by chemical spray pyrolysis technique (CSPT). Nd and Ce
doped vanadium oxide films were prepared, adding Neodymium
chloride (NdCl3) and ceric sulfate (Ce(SO4)2) of 3% in separate
solution. These precursor solutions were used to deposit un-doped
V2O5 and doped with Nd and Ce films on the p-type Si (111) and
glass substrate at 250°C. The structural, optical and electrical
properties were investigated. The X-ray diffraction study revealed a
polycrystalline nature of the orthorhombic structure with the
preferred orientation of (010) with nano-grains. Atomic force
microscopy (AFM) was used to characterize the morphology of the
films. Un-do

Undoped and Iodine (I)–doped chrome oxide (Cr2O3)thin films have been prepared by chemical spray pyrolysis technique at substrate temperatures(773K) on glass substrate. Absorbance and transmittance spectra have been recorded as a function of wavelength in the range (340-800 nm) in order to study the optical properties such as reflectance, Energy gap of allowed direct transition, extinction coefficient refractive index, and dielectric constant in real and imagery parts all as a function of wavelength. It was found that all the investigated parameters affect by the doping ratios.

Solutions of dyes Rhodamine 6G (Rh6G) and Coumarin480(C480) were prepared at five concentrations (1x10-3, 5x10-4, 1x10-4, 5x10-5 and1x10-5) mol/l, the mixing was stirred to obtain on a homogenous solution, the(poly methyl-methacrylate) (PMMA) was solved by chloroform solvent with certain ratio, afterward (PMMA+Rh6G) and (PMMA+C480) thin films were prepared by casting method on glass block which has substrate with dimensions (7.5 x2.5)cm2, the prepared samples were left in dark place at room temperature for 24 hours to obtain uniform and homogenous thin films. UV-VIS absorption spectra, transmission spectra and fluorescence spectra were done to measure linear refractive index and linear absorption coefficient. The nonlinear optical proper

In this work  Polyynes was synthesized by pulse laser ablation of graphite target in ethanol solution. UV-Visible Spectrophotometer, Fourier Transform Infrared Spectroscopy (FTIR) and Transmission electron microscopy (TEM) were used to study the optical absorption, chemical bonding, particle size and the morphology.  UV absorption peaks coincide with the electronic transitions corresponding to linear hydrogen – capped polyyne (C_n+1H₂), the absorption peaks intensity increased when the polyynes were produced at different laser energies and the formation rats of polyynes increased with the increasing of laser pulse number. The FTIR absorption peak at 2368.4 cm^-1, 1640.0 cm^-1 and 1276.

Functionalized-multi wall carbon nanotubes (F-MWCNTs) and functionalized-single wall carbon nanotubes (F-SWCNTs) were well enhanced using CoO Nanoparticles. The sensor device consisted of a film of sensitive material (F-MWCNTs/CoONPs) and (F-SWCNTs/CoO NPs) deposited by drop- casting on an n-type porous silicon substrate. The two sensors perform high sensitivity to NO₂ gas at room temperatures. The analysis indicated that the (F-MWCNTs/CoONPs) have a better performance than (F-SWCNTs/CoONPs). The F-SWCNTs/CoONPs gas sensor shows high sensitivity (19.1 %) at RT with response time 17 sec, while F-MWCNTs/CoONPs gas sensor show better sensitivity (39 %) at RT with response time 13 sec. The device shows a very reproducible sensor p

The optical energy gap and optical constants such as the reflective index, dielectric constant have been evaluated due to The optical transmission and UV-VIS absorption spectra have been recorded in the wavelength (200 - 1100 nm) for PVA/PANI polymer blends and PVA/PANI/ZnO nanocomposites with different concentrations of ZnO (0.02, 0.05, 0.07, 0.1and 0.2) wt %. The results indicate that the materials have allowed direct transition. The reflection index and dielectric constant are increase with wavelength

Zinc oxide nanoparticles (ZnO NPs) were created using two different preparation methods: chemical precipitation and the green method using the leaves of Ficus carica extract. The nanoparticles were examined using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and Energy Dispersive X-ray Spectroscopy (EDX). Analytical techniques such as XRD were applied to verify the crystallinity of ZnO NPs as well as used to calculate the crystal size for the prepared samples. The XRD pattern exhibited a hexagonal structure, and the mean diameter of the crystal size for ZnO NPs prepared by chemical precipitation was 27.44 and 33nm for ZnO NPs prepared by the biological method. Nanoparticles of Zn

This study evaluated the relationship between the blood glucose level, maximal standardized uptake value (SUVmax), and 18F-FDG uptake in tissues at normal and tumour organs with positron emission tomography/computed tomography (PET/CT) examinations. On the morning of the procedure, finger-stick fasting blood glucose is routinely assessed. The study looked at the SUVmax in the liver and bone of 200 people with F-FDG PET/CT scans for tumors and healthy organs¹⁸. The study formed three groups of patients based on their serum glucose levels. The study retrospectively examined the relationship between glucose levels and standardized uptake values. The mean liver and bone SUV_max gradually decreased as blood glucose levels

The current study used satellite data and geographic information systems to detect changes in land use and land cover and also studied climate factors, temperature, and humidity in the city of Amara, which is located in the southeast of Iraq, from 1990 to 2022. The study aimed to calculate the land use land cover (LULC) using satellite images from Landsat 5 TM, Landsat 8 OLI, and Landsat 9 OLI2, also from the Meteorological Service; temperature and humidity data were used to calculate the THI index. Iraq was one of the nations most exposed to the altering climate as a result of global warming and its effects. There was an urgent need to research climate change and land use in Amara city as temperatures rose and the city experienced droug

The OI-LED device was created through the utilization of a blend of organic and inorganic semiconductors arranged in multiple layers. This has led to an enhanced generation of electroluminescence (EL) by integrating Carbon Nanoparticles (CNp) (sized between 20-40 nm) into materials like poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butylphenyl)diphenylamine)] (TFB and Tris(8-quinolinolato)aluminum(III) (Alq3). The manufacturing procedure included the application of the spin coating method and phase segregation technique, resulting in a thin film structure: (ITO/TFB/CNp/Alq3/AL). The electroluminescent characteristics of the OI-LED were analyzed by assessing the variations induced by different bias voltages (8, 9, and 10V) and

This study aims to enhance the corrosion resistance of carbon steel (45 alloys) in saline water (3.5% NaCl) by applying a polymer nanocomposite coating. The nanocomposite was synthesized by integrating nickel oxide (NiO) and vanadium oxide (V₂O₅) nanoparticles, produced via a green synthesis method using moringa extract, into a polyacrylonitrile (PA) matrix. The coating's performance was evaluated across a range of temperatures: 293, 303, 313, and 323 K, achieving an inhibition efficiency of up to 89% at 303 K. The created nanocomposites were carefully examined using various testing methods, such as atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray d

This study used the green method to synthesise zinc oxide nanoparticles by microwave irradiation, using plant extracts of tea, coffee, and rosemary separately and Zn(NO₃)₂.6H₂O; this method is considered eco-friendly, rapid, and cost-effective. The structural properties of prepared materials were investigated with an X-ray diffractometer (XRD), atomic force microscope (AFM), Fourier transform infrared (FT-IR) spectroscope, and field emission scanning electron microscope (FE-SEM). Energy Dispersive X-ray (EDX) analysis was used to prove the presence of ZnO NPs. The electrical charge of the surface of nanomaterials was measured by Zeta potential, where 20 mV is adequate for ensuring physical stability. The three green extracts (tea,

In this research, iron oxide (Fe₂O₃) nanoparticles were doped with 5% mol of metallic material silver (Ag) and non-metallic material sulfur (S) by a wet impregnation process. Scanning electron microscopy (SEM) was used to determine the shape and arrangement of the crystals. UV-Vis spectroscopy was used to study the photocatalytic degradation of dye pollutants by measuring the absorbance spectra of the Ag/Fe₂O₃ and S/Fe₂O₃ nanoparticle samples. The objective of this study was to investigate the impact of pH on the photocatalytic activity of nanoparticles. The pH of a 5ppm solution of methylene blue (MB) dye was changed to 3 and 8 using hydrochloric acid (HC

This research shows how to prepare polyvinyl alcohol (PVA) films with silver nanoparticles and how different amounts of these nanoparticles affect the films' properties. The silver nanoparticles (AgNPs), featuring a uniform spherical shape, were synthesised using the chemical reduction method. The concentration of AgNPs and the amount of the reducing agent were found to influence the structural and optical characteristics of the prepared films. Higher volumes of the reducing agent have resulted in the formation of larger silver nanoparticles. These factors affected the size of the silver nanoparticles and the specific absorption peak, which was between 420 and 435 nm, with the nanoparticles measuring between 20 and 32 nm in size

Cadmium selenide (CdSe) nanocrystals, modified with water-soluble L-cysteine and known as CdSe/Cys nanocrystals, were synthesized using L-cysteine as a stabilizing agent. This synthesis process ensured the formation of highly stable nanocrystals with desirable properties for various applications. The CdSe/Cys nanocrystals were carefully studied using advanced methods to understand their structure, composition, and optical features in detail. The peak that shows the preferred (111) orientation of L-cysteine-capped CdSe matches the usual core components, as indicated by the XRD pattern. On the other hand, the peaks at (220) and (311) are not as prominent. Photoluminescence (PL) spectroscopy was conducted to study the optical properties of

In this work, Ag and Ag@Cr nanoparticles were fabricated utilizing the plasma jet and chemical spray deposition approach to produce thin films of Ag and Ag@Cr. The optimal gas-detecting properties can be achieved by varying the ratios of Ag@Cr (4:6, 2:8, 3:7) ml and 10 ml Ag. XRD, transmission electron microscopy (TEM), and UV-Vis spectroscopy were used to characterize the Ag and Ag@Cr thin films. Additionally, an absorption peak appears at 422 nm for Ag, and the absorption peaks for Ag@Cr are at 408, 413, and 410 nm, with a polycrystalline character as seen from the XRD pattern. The gas NO₂ was used to check how sensitive, responsive, and quickly recoverable the Ag and Ag@Cr nanocomposite thin films are. According to the findings, at

Over the past few years, there has been a significant focus on studying the synthesis and applications of metal nanoparticles. These tiny particles possess distinct properties that set them apart from bulk metals. The liquid for Cr:Se core-shell nanoparticles was made using the plasma jets method and turned into thin films that are 158.9 nm thick through chemical spray pyrolysis. The nanothin films were analyzed using X-ray diffraction (XRD), ultraviolet-visible spectroscopy, and transmission electron microscopy (TEM). This study looks at the structure and light properties of core-shell nanoparticles made with a chromium to selenium (Cr:Se) ratio of 6:4. The XRD patterns confirmed the crystalline nature of the nanoparticles for the polyc

In this study,  thin films of pure and aluminum (Al)-doped zinc oxide/polymethyl methacrylate (ZnO/PMMA) with two different amounts (5% and 7%) using the sol-gel and spin coating methods were created and then heated at two temperatures (450 and 750°C). Many characteristics were used to analyze the resulting samples, including X-ray diffraction (XRD), UV-visible, and infrared (IR) absorption spectroscopy. The X-ray diffraction analysis of the samples indicated that they formed a hexagonal structure of ZnO known as wurtzite, with a preferred direction labelled as (101). UV-visible analysis of the specimens' optical characteristics has helped calculate the gap energy using the Tauc method. The energy value is 4.12 eV. The optical characte

This study analyzes long-term trends in temporal data from 1980 to 2020, encompassing four decades to assess the impacts of climate change on the environment and ecosystems. The NASA power data access viewer provided data, including wind, temperature, solar radiation, atmospheric pressure, precipitation, and humidity. Statistical analysis methods, including trend analysis and ANOVA, were utilized to evaluate the disparities among time courses. Linear regression models were employed to conduct trend analysis for each decade, assessing changes in climate parameters. An analysis of variance (ANOVA) was performed over four decades. The findings demonstrate that no statistically significant differences exist in the examined climate parameters

The study included preparing pure polyaniline (PANI) and treating it with sulfuric acid at various strengths while keeping the temperature at 27ºC. The morphology of the polymerization products was examined using a scanning electron microscope (SEM). The SEM images revealed a notable effect of how much acid is present on the formation of PANI. The investigation focused on the relationship of alternating electrical conductivity with temperature and frequency. The A.C. electrical conductivity was represented by the variable (s) and varied with frequency, which ranged from 1 kHz to 10 MHz. The value of s was found to be less than 1, and it decreased as the temperature increased. This observation implies a dominant hopping mechanism. The ac

The study used the optical emission spectroscopy method to present the effect of changing doping ratios and laser energy on plasma parameters. Plasma spectra were acquired across energy levels by zinc oxide combined with nickel oxide (ZnO_X: NiO_1-X) at x = 0.3, 0.5, and 0.7. The analysis of these airborne mixtures was carried out through the application of spectroscopy. The electron temperature results indicated that the range for x=0.3 was 0.446-0.491 eV, for x=0.5 was 0.470-0.486 eV, and for x=0.7 it was 0.474-0.489 eV. Differences in electron temperatures between compositions can lead to new technological applications and comprehension of physical phenomena. It was found that when the proportion of doping was incr

In this work, the plasma parameters (electron temperature and
electron density) were determined by optical emission spectroscopy
(OES) produced by the RF magnetron Zn plasma produced by
oxygen and argon at different working pressure. The spectrum was
recorded by spectrometer supplied with CCD camera, computer and
NIST standard of neutral and ionic lines of Zn, argon and oxygen.
The effects of pressure on plasma parameters were studied and a
comparison between the two gasses was made.