The application of novel core-shell nanostructure composed of Cu, Ag, Au/NiO to improve the sensitivity of pure NiO to H2S gas sensors is demonstrated in this study. The growth of Cu, Ag, Au/NiO core-shell nanostructure is performed by chemical reaction of NiO on metal nanoparticle (Cu, Ag and Au) that prepared by pulsed laser ablation (PLA( technique. This is to form the homogeneous structure of the sensors investigated in this report to assess their sensitivity in terms of H2S detection. These novel H2S gas sensors were evaluated at operating temperatures of 25 °C, 100 °C and at 150 °C. The result reveals the Cu, Ag, Au/NiO core-shell nanostructure present a good sensitivity at low working temperatures compared by pure NiO nanoparticles. These core-shell nanostructure sensors also possess the highest response (<32 s) and recovery (<28 s) values with greater repeatability seen for H2S sensors at low temperatures, unlike traditional sensors that only work effectively at much higher temperatures. The data in this study indicates the newly-developed Cu, Ag, Au/NiO core-shell nanostructure based sensors are highly promising for industrial applications.
The mixed ligand complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) with alanine and 8-hydroxyqinoline (Oxine) were synthesized and characterized by FT-IR ,spectra electronic, flam-AAS] along with conductivity measurements , solubility , melting point, magnetic susceptipibility.The synthesized complexes were tested in vitro for antimicrobial activity. The results obtained indicated that some of these complexes are more active than with others.
A new series of transition metal complexes of Cu(II), Ni(II), Co(II) and Fe(III) have been synthesized from the Schiff base (L1) and (L2) derived from Semicarbazide hydro chloride and 4-chlorobenzaldehyde or 4-bromobenzaldehyde. The structural features have been arrived from their elemental analyses, magnetic susceptibility, molar conductivity, IR, UV-Vis. and 1H NMR spectral studies. The data show that the complexes have composition of [M(L)2](NO3)2 and [Fe(L)2 (NO3)2](NO3) where the M=Co(II),Ni(II) and Cu(II) ;L=L1and L2 type. The magnetic susceptibility and UV-Vis spectral data of the complexes suggest a square planer geometry for Co(II) and Cu(II) but Fe(III) octahedral geometry and Ni(II) tetrahedral geometry around the central metal i
... Show MoreThis study is a trail to know if the genes controlling some of heavy metals resistance ( lead, zinc, cadmium, cromium) in two types of pathogenic bacteria E. coli as gram negative bacteria and S. aureus as gram positive bacteria, present on the β-lactamase plasmid. Ten isolates of each bacterial types which produced β-lactamase enzyme, were cultivated in the presence of acridine orange. The growing in the presence of acridine orange resulted in loss of the β-lactamase genes in S. aureus and E. coli, and loss of the heavy metals resistance in S. aureus, while the resistance of E. coli against heavy metals still without any change. The results indicate that the genes for heavy
... Show MoreRoad-side dust samples were collected during August in 2020 from selected areas of, Al-Rusafa, Baghdad, Iraq. A sedimentological and mineralogical analysis of street dust was conducted. Three areas were selected to study street dusts which are Al-Baladitat, Al-Obaidi and Ziona. The laboratory analyses were done in the Department of Geology, College of Science, University of Baghdad. The heavy metal contents were determined in the roadside dust using XRF Method. It was found that the dust is of muddy texture, and is believed to be transmitted with the various storms blowing on Baghdad or by the wheels of Cars. The results of mineralogical investigation revealed that the dust samples composed of quartz, feldspar, calcite, gypsum and s
... Show MoreAbstract. Al-Abbawy DAH, Al-Thahaibawi BMH, Al-Mayaly IKA, Younis KH. 2021. Assessment of some heavy metals in various aquatic plants of Al-Hawizeh Marsh, southern of Iraq. Biodiversitas 22: 338-345. In order to describe the degree of contamination of aquatic environments in Iraq, heavy metals analysis (Fe, Ni, Cr, Cd, Pb, and Zn) was conducted for six aquatic macrophytes from different locations of Al-Hawizeh Marsh in southern Iraq. The six species were Azolla filiculoides (floating plant), Ceratophyllum demersum, Potamogeton pectinatus, Najas marina (submerged plants), Phragmites australis, and Typha domingensis (emergent plants). The results indicate that cadmium, chromium, and iron concentrations in aquatic plants were above the
... Show MoreThe measurements of major and trace elements in different brands of milk powder selected from the Iraqis market via the X-ray fluorescence (XRF) Technique have been studied in the present work. The result of the measurements reveals the high concentrations of sodium, phosphorus, sulfur, chlorine, potassium, calcium and magnesium. Furthermore, low concentrations of aluminum, silicon, iron, bromine, molybdenum, iodine, barium, titanium, manganese, cobalt, chrome, nickel, copper, zinc and lead were detected. Neutron activation analysis (NAA) and Kjeldahl technique were also employed to determine the concentrations of nitrogen. It was found that the nitrogen concentration was in the range of (1.96 - 3.23) % which is within the permissible li
... Show MoreVarious heavy metals, cations and anions of the Tigris River water in Baghdad regionwere studied during the winter, spring, summer and autumn of 2009, for 4 samplingsites. In the present investigation the levels of studied heavy metals, cations and anionswere found in the range of (0.011-0.333 mg/L) for As, in the water samples(undetectable-0.0043 mg/L) for Sb,( 0.011-0.080 mg/L) for Ti, (0.150-0.730 mg/L) forV, (0.01-1.06 mg/L) for Fe, (0.1-0.4 mg/L) for Zn, (0.011-0.15 mg/L) for Pb, (0.01-0.05mg/L) for Cd, (0.01-0.04 mg/L) for Ni, (50-290 mg/L) for Ca, (97-270 mg/L) for Mg,(0.65-1.74 mg/L) for K, (11-38.33) for Na, (35-113 mg/L) for Cl, (150-256 mg/L) forHCO3, (96-479 mg/L) for SO4, (0.93-3.9 mg/L) for NO3 and (undetectable - 0.360 mg/L)f
... Show MorePetroleum is one of the most important substances consumed by man at present times, a major energy source in this century, petroleum oils can cause environmental pollution during various stages of production, transportation, refining and use, petroleum hydrocarbons pollutions ranging from soil, ground water to marine environment, become an inevitable problem in the modern life, current study focused on bioremediation process of hydrocarbons contaminants that remaining in the bottom of gas cylinders and discharged to the soil. Twenty-four bacterial isolates were isolated from contaminated soils all of them gram negative bacteria, bacterial isolates screening to investigate the ability of biodegradation of hydrocarbons, these isolates inocula
... Show MoreBlades of gas turbine are usually suffered from high thermal cyclic load which leads to crack initiated and then crack growth and finally failure. The high thermal cyclic load is usually coming from high temperature, high pressure, start-up, shut-down and load change. An experimental and numerical analysis was carried out on the real blade and model of blade to simulate the real condition in gas turbine. The pressure, temperature distribution, stress intensity factor and the thermal stress in model of blade have been investigated numerically using ANSYS V.17 software. The experimental works were carried out using a particular designed and manufactured rig to simulate the real condition that blade suffers from. A new cont
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