The aim of this study is to investigate the antibacterial capabilities of different coating durations of three nanoparticle (NP) coatings: molybdenum (Mo), tantalum (Ta), and zinc oxide (ZnO), and their effects on the surface characteristics of 316L stainless steel (SS). The coated substrates underwent characterization utilizing field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffractometer (XRD) techniques. The antibacterial efficacy of NPs was evaluated using the agar diffusion method. The FE-SEM and EDX images confirmed the presence of nano-sized particles of Mo, Ta, and ZnO on the surface of the substrates with perfectly symmetrical spheres and a uniform distribution of the NPs. All groups demonstrated antibacterial activity, and the ability to inhibit the growth of Streptococcus mutans and Lactobacillus acidophilus bacteria. The ZnO group had the most potent antibacterial effect, followed by the Mo group, while the Ta group had the least effect. A direct-current (DC) plasma sputtering system was used to produce nano-coatings of high purity that were homogeneous, crack-free and showed no sign of delamination. Bacterial strains exposed to Mo, Ta, and ZnO coated surfaces exhibited a significant loss of viability in a time-dependent manner. The optimum sputtering time to ensure the best antibacterial properties and preserve the resources was 1 hour (h) for Mo, 3 h for Ta and 6 h for ZnO.
Eleven yoghurt samples were collected from local markets in Baghdad to isolate Lactobacillus buchneri. Only 3 isolates of L. buchneri were found and the isolate No. 3 was the most producer of bacteriocin. Bacteriocin was adsorbed 100% onto silicic acid at pH 6.0-7.0. Below or above these pH values, adsorption was decreased, ranging between 35 and 90%. Therefore, pH 6.0 was used for the purification procedure. The purification procedure including silicic acid adsorption/desorption and cation-exchange chromatography (CEC) resulted in a 11.11 fold increase in the final specific activity of pure bacteriocin (1176.47 Au/mg) compared to the culture supernatant which was 32.64 Au/mg. The molecular weight was determined to be about 3.4 kDa. The bac
... Show MoreCoumarin derivatives have shown different biological activities, such as antifungal, antibacterial antiinflammatory, and antioxidant activities, besides antibiotic resistance modulating effects, and anti-HIV, hepatoprotective, and antitumor effect. So, new coumarin derivatives (hydrazones and an amide) were synthesized through multisteps reactions. All the synthesized target compounds were characterized by FT-IR spectroscopy, 1HNMR analysis. The compounds then evaluated for their anti-bacterial activity by means of well-diffusion method against two gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae) and two gram-negative bacteria (E.coli and Pseudomonas aeruginosa). The highest activity was demonstr
... Show MoreA total of four types of instant dry yeast
This study was conducted in a lath house, Dept of Hort. and Landscape, College of Agricultural Engineering Sciences, Univ. During the 2021 growing season, Baghdad will investigate the influence of organic and Biological fertilizers on three Citrus rootstocks' growth and leaf mineral content. The first factor is the addition of liquid organic fertilizers Vit-Org (O) at three levels without addition (O0), soil addition at 10 ml.L-1 (O10) and soil addition at 20 ml.L-1 (O20). The second factor is the addition of nitrogen-fixing bacteria without addition (N1), add 30 ml.Transplant-1 of Azotobacter chroococcum (N2) and add 30 ml.Transplant-1 of Azospirillum brasilemse (N3). The third factor is three citrus rootstocks: sour orange (R1), R
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The present investigation deals with experimental study of three-phase direct-contact heat exchanger, for water-Freon R11 system, where water is the continuous phase (liquid) and Freon R11 (liquid-gas) is the dispersed phase. The test section consisted of a cylindrical Perspex column with inner diameter 8cm and 1.2m long, in which, water was to be confined. Liquid Freon R11 drops were injected into the hot water filled column, through a special design of distributors at the bottom of the column. The liquid Freon R11 drops rose on their way up and evaporated into two-phase bubbles at atmospheric pressure. The study was devoted to express the effect of process variables such as c
... Show MoreThis paper aims to validate a proposed finite element model to be adopted in predicting displacement and soil stresses of a piled-raft foundation. The proposed model adopts the solid element to simulate the raft, piles, and soil mass. An explicit integration scheme has been used to simulate nonlinear static aspects of the piled-raft foundation and to avoid the computational difficulties associated with the implicit finite element analysis.
The validation process is based on comparing the results of the proposed finite element model with those of a scaled-down experimental work achieved by other researchers. Centrifuge apparatus has been used in the experimental work to generate the required stresses to simulate t
... Show MoreRestoration of degraded lands by adoption of recommended conservation management practices can rehabilitate watersheds and lead to improving soil and water quality. The objective was to evaluate the effects of grass buffers (GBs), biomass crops (BCs), grass waterways (GWWs), agroforestry buffers (ABs), landscape positions, and distance from tree base for AB treatment on soil quality compared with row crop (RC) (corn [