It is often noted that disordered materials have different chemical properties to their more “ordered” cousins. Quantifying these effects in terms of thermodynamics is challenging in part because disordered materials can be difficult to characterize and are frequently relatively unstable. During the course of our experiments to understand the effects of disorder in catalysts for water oxidation we observed that many disordered manganese and cobalt oxide water oxidation catalysts directly oxidized peroxide in contrast to their more ordered analogues which catalyzed its disproportionation, that is, MnO2+2H+ +H2O2! Mn2+ +2H2O+O2(oxidation) versus H2O2!H2O+1=2 O2(disproportionation). By measuring the efficiency for one reaction over the other as a function of pH, we were able to quantify the relative stability of materials in two series of metal oxides and thereby quantify their relative thermodynamic stability, “by proxy”. We found that for the series of catalysts investigated the disorder made the materials stronger chemical oxidants and worse catalysts for the disproportionation of peroxide
Background: Glass ionomers have good biocompatibility and the ability to adhere to both enamel and dentin. However, they have certain demerits, mainly low tensile and compressive strengths. Therefore, this study was done to assess consistency and compressive strength of glass ionomer reinforced by different amount of hydroxyapatite. Materials and Methods: In this study hydroxyapatite materials were added to glass ionomer cement at different ratios, 10%, 15%, 20%, 25% and 30% (by weight). The standard consistency test described in America dental association (ADA) specification No. 8 was used, so that all new base materials could be conveniently mixed and the results would be of comparable value and the compressive strength test described by
... Show MoreIn this research, the Boiti–Leon–Pempinelli (BLP) system was used to understand the physical meaning of exact and solitary traveling wave solutions. To establish modern exact results, considered. In addition, the results obtained were compared with those obtained by using other existing methods, such as the standard hyperbolic tanh function method, and the stability analysis for the results was discussed.
The aim of this study is to evaluate in-vitro activity of Cefamandol (Cfm) and Ceftazidime (Cfz), in combination with Clavulanic acid (CA) against ten complicated multiresistant uropathogenic E.coli .One hundred clinical strains were isolated from patients with chronic urinary tract infections (UTIs), these isolates were identified by the Api identification systems. The antimicrobial susceptibility tests were determined by Kirby-Bauer method, all of them were sensitive to Imipenem (Imp). Ten strains were chosen for the present study, they were resistant to Ampicillin (Amp), Amoxicillin (Amo), Carbenicillin (Cb), Ticarcillin (Tic), Azlocillin (Azl), Amoxicillin\ Potassium Clavulanate {Augmentin(Amc)}, (Amo\CA), Ticarcillin\ Potas
... Show MoreHighway embankments stability during its service period represents an important factor for the safety of highway users and vehicles. Consequently, the cost of construction of these embankments should be adequate to maintain the safety and durability during this period through proper estimation of the loading on asphalt pavement, slope stability, horizontal and vertical deformation, etc. Slope stability of the embankment mainly depends on the shear strength of the soil layers materials; this shear strength is affected by the water table level through the contribution of the capillary water. Negative pore water pressure above the water table level evolves matric suction in the unsaturated zone above water table; this matric suction increases
... Show MoreIn the present study a new synthesis method has been introduced for the decoration of platinum(Pt) on the functionalized graphene nanoplatelet (GNP) and also highlighted the preparation method of nanofluids. GNP–Pt uniform nanocomposite was produced from a simple chemical reaction procedure, which included acid treatment for functionalization of GNP. The surface characterization was performed by various techniques such as XRD, FESEMand TEM. The effective thermal conductivity, density, viscosity, specific heat capacity and stability of functionalized GNP–Pt water based nanofluids were investigated in different instruments. The GNP–Pt hybrid nanofluids were prepared by dispersing the nanocomposite in base fluid without adding any surfac
... Show MoreThe aim of this work was directed to measure the cosmic ray (CR)
flux and the background (BG) absorbed dose rate for districts of
Baghdad city. The maximum values of CR flux was 2.01
(particle/cm2.s) registered for several Baghdad districts and the
minimum was 0.403 (particle/cm2.s) belonging to Al-kadhimiya
district, whereas the overall average value was 1.24 (particle/cm2.s).
The BG measurements showed that the maximum absorbed dose was
25 nSv/h belonging to Noab AL-Dhbat district and the minimum
absorbed was 19.01 nSv/h observed in Al-Ghadeer district, while
the overall average was 22.56 nSv/h, and this value is small than the
Iraqi permissible limit, which is restricted by Iraqi Center of
Radiation Pr
Abstract. In this research, the uranium concentration in (16) water samples collected from some agricultural areas surrounded with AlTuwitha nuclear site in Baghdad-Iraq was measured by using a CR-39 detector. The concentration of uranium in this study was from (0.6 ± 0.33mg/l) to (2.51 ± 0.49 mg/l), and the weighted average for the concentrations (1.262 ± 0.402 mg/l). The results showed it is a concentration of uranium level in water samples studied is higher than the allowed limit recommended by WHO and ICRP.
This study was conducted in the plant protection department/ College of Agriculture/ University of Baghdad to evaluate the efficiency of physical agents ozone, ultraviolet radiation, microwave for destroying afla produced in corn seeds. An isolate af A.flavus producing Aflatoxin B1 was obtained from plant protection dept. college of Agric. University of Baghdad. Results showed destroy toxin AFLA B1 the effect of radiation microwave in the media of Japex degree 80 and 100 co 57.14% and 85.71%, respectively, and for 20 sec, compared to the treatment comparison 0.00% as found significant differences were apparent between transactions and the treatment of comparison, as and notes the existence of a significant dif
... Show MoreBackground : The dermatophytesare taxonomically related fungi causing different skin infections referred to as tineas in man or ringworm in man and animals . Objective:This study was established to investigate theof effect of yellow sap and gel of Aloe vera on skin of the rabbits which infected with T.verrucosum. Methods : Twelveskin biopsy were taken from rabbits for histopathological study to know the the effects of the T.verrucosumand treated with yellow sap and gel. Results : the results of histopathological study of effect of yellow sap and gel of Aloe vera on skin of the rabbits which infected with T.verrucosum showed the concentration of the gel of aloe vera at 75% was more effected to treat the infective area of skin with T.verrucos
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