In this research, a novel thin film Si-GO10 and nanopowders Si-GO30 of silica-graphene oxide (GO) composite were prepared via the sol–gel method and deposited on glass substrates using spray pyrolysis. X-ray diffraction (XRD) results showed a relatively strong peak in the graphite layer that corresponds to the (002) plane. Transmission electron microscope (TEM) images showed that SiO2 nanoparticles were randomly distributed on the surface of GO plates, and the particle size in these nanopowders was below 50 nm. Field emission scanning electron microscopy (FESEM) analysis demonstrated that silica nanoparticles on the surface of GO plates exhibited almost spherical and rod-like nanoparticle shape, which in turn confirmed the formation of SiO2–GO nano-hybrids. Photocatalytic investigations revealed that the composite materials exhibit high activity for dye adsorption and decomposition. Si-GO10 thin film did not undergo degradation after 120 min; however, for Si-GO30 nanopowder, the adsorption peak intensity was reduced to 665 nm, indicating a decrease in the dye concentration in the solution. Fourier transform infrared scan (FTIR) analysis demonstrated that carboxylic functional groups are decreased by increasing silica particles. Photoluminescence (PL) spectrum in Si-GO10 thin film showed a sharp emission peak at about 665 nm. This spectrum completely disappeared in Si-GO30 nanopowders. Results of the antibacterial properties emphasized that Si-GO30 nanoparticle would prevent Escherichia coli growth after 20 h. The presented methodology allows for the synthesis of GO supported silicon dioxide nanoparticles for promising applications in photocatalytic and antibacterial fields.
Adsorption capacity of a waste biomass, date stones, for phenolic compounds such as phenol (Ph) and p-nitro phenol (PNPh) was investigated. The characteristics of such waste biomass were determined and found to have a surface area and iodine number of 495.71 m²/g and 475.88 mg/g, respectively. The effects of temperature, initial sorbate concentration, and contact time on the adsorption process were studied. Experimental equilibrium data for adsorption of Ph and PNPh on date stones were analyzed by the Langmuir, Freundlich and Sips isotherm models. The results show that the best fit was achieved with the Sips isotherm equation with maximum adsorption capacities of 147.09 and 179.62 mg/g for Ph and PNPh, respectively. The kinetic data wer
... Show Moreعانت الغابات في العراق قصوراً واضحاً في مجال إشباع حاجة السكان لمنتجاتها الرئيسية المتمثلة بالأخشاب ومنتجاتها الثانوية المتمثلة بالأغصان والأوراق والنباتات الطبيعية والحيوانات البرية ونواتجها الأخرى، مما يتطلب التفكير بمحاولة إيجاد سبل جديدة لحل هذه المشكلة الاقتصادية المرتبطة بعنصريها الحاجة للأخشاب والأموال المخصصة لتطويرها عموماً.
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... Show MoreThe target of this study was to study the natural phytochemical components of the head (capsule) of Cynara scolymus cultivated in Iraq. The head (capsule) of plant was extracted by maceration in70% ethanol for 72 hours, and fractioned by hexane, chloroform and ethyl acetate. Preliminary qualitative phytochemical screening was performed on the ethyl acetate fraction for capsule was revealed the presence of flavonoid and aromatic acids. These were examined by (high -performance liquid chromatography) (HPLC diodarray), (high- performance thin-layer chromatography)(HPTLC).
Flavonoids were isolated by preparative layer chromatography and aromatic acid was isolated by preparative high-
... Show MoreBacopa monnieri L. (Scrophulariaceae), synoname is Herpestis monniera that provides bioactive compounds, especially triterpenoid saponins (Bacosides) which exhibits an important biological activities, like hypothyroidism, anticonvulsant, memory enhancing and antistress. Because there are no researches about B. monnieri L. plant that grow in Iraq, and there active compounds especially triterpenoid saponin (TS), and there effects. This study was detected the presence of (TS) in, and examined the cytotoxic and the antioxidant activity of these compounds in vitro. The study was included the extraction and identification of TS from the whole parts of B. monnieri L. by using three methods, and the best yield was analyzed by High Performance Liqui
... Show MoreThe ionospheric characteristics exhibit significant variations with the solar cycle, geomagnetic conditions, seasons, latitudes and even local time. Representation of this research focused on global distribution of electron (Te) and ion temperatures (Ti) during great and severe geomagnetic storms (GMS), their daily and seasonally variation for years (2001-2013), variations of electron and ion temperature during GMS with plasma velocity and geographic latitudes. Finally comparison between observed and predicted Te and Ti get from IRI model during the two kinds of storm selected. Data from satellite Defense Meteorological Satellite Program (DMSP) 850 km altitude are taken for Te, Ti and plasma velocity for different latitudes during great
... Show MoreThe current research reports the preparation and fabrication of the silver paste conductor which is employed as a soldering material for electro – optical components ohmic interconnections. The prepared paste possesses electrical characteristics identical to the ohmic connectors as its observable from resistance – temperature variation. Moreover, the I – V characteristics obeys Ohm’s law and this dependency was further confirmed by the nearly constant capacitance measurements with voltage and frequency. A noticeable improvement in electrical conductivity, compared to the pure silver paste sample, was noted for samples prepared by mixing predetermined weight ratios of brass and copper. Furthermore, stability of electrical resistan
... Show MoreBalance is considered one of the most important components of physical activity in individual and team sports because it allows proper motor response and performance accuracy. The problem of the research lies in the lack of model for motor balance tests in the field of sports that require different positions and movements for classifying, selecting, diagnosing, and comparing athletes. The importance of the research lies in designing a test for motor balance as a reference for specialists in the field of sports and sport sciences. The subjects were first year College of physical education and sport sciences students / Baghdad University 2016 – 2017. The data was collected and treated using proper statistical operations. The researchers con
... Show MoreAbstract
Backgrounds: Jaundice occurs in most newborn due to increased bilirubin concentration. Jaundice is observed during the first week after birth in approximately 60% of term neonates. A high level of bilirubin is neurotoxic and may cause neonatal kernicterus, auditory neuropathy or death.
Objectives: to compare the Rh group compatibility, serum bilirubin (total and direct), serum albumin and several liver enzymes between physiological and pathological neonatal jaundice
Materials and Methods: A cross sectional study for one hundred neonates with jaundice divided into group 1: 50 newborns with physiological jaundice, Group 2: 50 newborns with
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