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
Although its wide utilization in microbial cultures, the one factor-at-a-time method, failed to find the true optimum, this is due to the interaction between optimized parameters which is not taken into account. Therefore, in order to find the true optimum conditions, it is necessary to repeat the one factor-at-a-time method in many sequential experimental runs, which is extremely time-consuming and expensive for many variables. This work is an attempt to enhance bioactive yellow pigment production by Streptomyces thinghirensis based on a statistical design. The yellow pigment demonstrated inhibitory effects against Escherichia coli and Staphylococcus aureus and was characterized by UV-vis spectroscopy which showed lambda maximum of
... Show MoreThis investigation aims to explore the potential of waterworks sludge (WS), low-cost byproduct of water treatment processes, as a sorbent for removing Congo Red (CR) dyes. This will be achieved by precipitating nano-sized (MgAl-LDH)-layered double hydroxide onto the surface of the sludge. The efficiency of utilizing MgAl-LDH to modify waterworks sludge (MWS) for use in permeable reactive barrier technology was confirmed through analysis with Fourier transform infrared and X-ray diffraction. The isotherm model was employed to elucidate the adsorption mechanisms involved in the process. Furthermore, the COMSOL model was utilized to establish a continuous testing model for the analysis of contaminant transport under diverse conditions. A st
... Show MoreThis research was conducted to measure the safety of heat stable enterotoxin a (STa) produced by enterotoxigenic Escherichia coli, through studying its toxic effect on mice since it showed a promising effect in reducing the proliferation of colorectal cancer cells. The cytogenetic effect was determined after giving five different doses (100, 200, 400, 800 and 1600)μg/Kg in comparison with negative (phosphate buffer saline / PBS) and positive (mitomycin C/ MMC, at doses of 2 and 5μg/Kg) controls on mouse bone marrow cells by employing the following parameters: mitotic index, chromosomal aberrations and micronucleus, also, the serum level of liver functional enzymes (GOT, GPT, ALP) was recorded. In addition, lethal dose 50 (LD 50) with cert
... Show MoreThe aim of this study was the production of aspartame by using immobilized thermolysin in bentonite clay. The yield of immobilized thermolysin in bentonite was 92% of the original enzyme amount. pH profile of free and immobilized enzyme was 7.0 and 7.5 respectively which was stable at 6.5-9.0 for 30min. The optimum temperature of both enzymes was 50°C, while they were stable at 65°C for 30min. however, they lost 52.73 and 61.72% from its main activity at 80°C respectively. Immobilized thermolysin has retained all activity within 27 days, but it kept 68.27% of initial activity when stored for 60 days at 4°C whereas, it retained a full activity after 20 continue usage. In addition, it retained 86.53% of its original activity af
... Show MoreThe major objectives of this research are to analyze the behavior of road embankments
reinforced with geotextiles constructed on soft soil and describe the finite element analysis by using
ANSYS program ver. (5.4). The ANSYS finite element program helps in analyzing the stability of
geo- structure (embankment) in varied application of geotextiles reinforcement to enhance the best
design for embankment.
The results of analysis indicate that one of the primary function of geotextiles reinforcement was to
reduce the horizontal displacement significantly. With the inclusions of reinforcement, the horizontal
displacement reduced by about (81%), while the vertical displacement reduced by (32%). The effect
of geotextiles
Societies developed throughout history with the development of life technology, that ideas presented by the contemporary art have been crystallized. The development included all the artistic fields such as the dramatic arts which depend on many effects and elements that led to the completion of the structure of the theater show. Scenography is considered one of the most important elements that the theatre show depends on such as the decoration, lighting, sound effects, costumes and accessories. The research addressed the following question: what are the characteristics and traits of scenography in the theatre show?
The research importance has become clear because it sheds lights on the characteristics of scenography in the Iraqi thea
The efficient removal of dissolved organic compounds (DOC) from wastewater has become a major environmental concern because of its high toxicity even at low concentrations. Therefore, a technique was needed to reduce these pollutants. Ion exchange technology (IE) was used with AmberliteTM IR120 Na, AmberliteTM IR96RF, and AmberliteTM IR402, firstly by using anion and mixed bed system, where the following variables are investigated for the process of adsorption: The height of the bed in column (8,10 and 14 cm), different concentrations of (DOC) content at constant flow rate. The use of an ion exchanger unit (continuous system) with three columns (cation, anion, and mixed bed) was studied.
... Show MoreNew complcxcof Cu (ll),Ni(ll) ,Co(ll), and Zn(ll) wi th 2- amino-5-p-Fiouro Phenyl 1,3,4-Thiadiazole have been synthesized . The products were isolated , studied and characterized by physical measurements, i.e., (Ff -IR) ,UV-Vis and the melting points were determined .The new Schiff base (L) has been used to prepare some complexes .The prepared complexes were identified and their tructural geometry were suggested.
New complexes of Cu (ll), Ni (ll), Co (ll), and Zn (ll) wi th 2-amino-5-p-Fiouro Phenyl 1, 3, 4-Thiadiazole have been synthesized. The products were isolated, studied and characterized by physical measurements, ie,(Ff-IR), UV-Vis and the melting points were determined. The new Schiff base (L) has been used to prepare some complexes. The prepared complexes were identified and their structural geometry were suggested