(28)Bacterial local isolates of Bacillus sp. were obtained from soil samples. Isolates were tested for thermostable alpha- amylase production on solid media; fifteen isolates were able to develop clear zone around the bacterial growth after floating the plates with iodine reagent (Lugol's solution). There were further tested in submerged culture which led to selection of Bacillus sp. H14since it was the most efficient .Microbial and biochemical tests showed that the local isolate Bacillus sp.H14was refered to the species B.licheniformis that signed as H14 was refered to the species B.licheniformis H14 .,To get ahigher yield of alpha – amylase(48.70unit/mg protein) production from the local isolate B.licheniformis H14 . This study used different mutation ways such as physical way by using the physical mutagen (ultraviolet light) and chemical way by using the chemical mutagen (nitrosoguanidine). Physical mutation results showed that the local isolate B.licheniformis HM14 get higher yield of alpha – amylase production(102.10 unit/mg protein) according to killing percentage (90%) while the chemical mutation results showed that the local isolate B.licheniformis HM4 get higher yield of alpha –amylase production(100.94 unit/mg protein) from the two mutant local isolates (HM14 and HM4)were the best carbon source starch (1.5%), peptone (1.5%) as nitrogen source, calcium chloride (0.02%), sodium chloride (0.05%), magnicium phosphate (0.05%), sodium di –hydrogen phosphate (0.16%), at initial pH (5) and inoculum size 1*108 cfu/ml at (50?C) For (72) hours, using shaking incubator at (150) rpm.
This paper reports an experimental study regarding the influence of vertical oscillations on the natural convection heat transfer from a vertical channel. An experimental set-up was constructed and calibrated; the vertical channel was tested in atmosphere at 25o
C. The channel-to-ambient temperature difference was varied with the power supply to the electrical heater ranging between
15W to 70W divided into five levels. Data sets were measured under different operating condition from a test rig under six vibrating velocities (VVs) levels ranging from (5-30 m/s) in addition to the stationary state. The results show that the maximum heat transfer enhancement factor (E) occurs at Rayleigh number (Ra=2.328×103 ) and vibrational Reynol
The present study revealed a low-cost process for utilizing desert sand for preparing nanosilica by sol-gel technique. This work required sodium hydroxide, concentrated hydrochloric acid, distillate water as raw materials, and Iraqi sand. Nanosilica sample was characterized by X-Ray Diffraction (XRD), scanning electron microscopy analysis (SEM), atomic force microscope(AFM), surface area (BET) method, and fourier transform infrared (FTIR). The XRD result of produced sample is referred to as amorphous silica, and it has a broad peak at 2Θ= 22° – 22.5 º. SEM showed spherical, agglomerated silica particles with a diameter range of 26.57–28.93 nm. In addition, the average particle size was 76.35nm, with a dimension range of 40-11
... Show MoreNitrogen dioxide NO2 is one of the most dangerous contaminant in the air, its toxic gas that cause disturbing respiratory effects, most of it emitted from industrial sources especially from the stack of power plants and oil refineries. In this study Gaussian equations modelled by Matlab program to state the effect of pollutant NO2 gas on area around Durra refinery, this program also evaluate some elements such as wind and stability and its effect on stacks height. Data used in this study is the amount of fuel oil and fuel gas burn inside refinery at a year 2017. Hourly April month data chosen as a case study because it’s unsteady month. After evaluate emission rate of the all fuel and calculate exit velocity from
... Show MoreIn this study, synthesis of polymer Nanocomposites through the blending of prepared polymers with polyvinyl alcohol (a synthetic polymer) or chitosan (a natural polymer) then mixed with nano oxide silica by many steps. The new compound [I] was obtained via reaction of 3,3’-dimethoxybiphenyl-4,4’-diamine as starting material with malic anhydride in DMF then treatment with ammonium persulfate (NH4 )2 S2 O8 (as the initiator) in order to produce polymer [II]. Also, we prepared new polymers [III-V] by using the same starting material (3,3’-dimethoxybiphenyl-4,4’-diamine) with glutaric acid or adipic acid or isophthalic acid in DMF and pyridine. In this study, new polymer blending [VI-IX] and [X-XIII] were synthesized from a prepared pol
... Show MoreA new series of 5-methoxy-2-mercapto benzimidazole derivatives were synthesized by the reaction of 5-methoxy- 2-mercaptobenzimidazole with chloroacetic acid and affords 2-((5-methoxy-1H-benzo[d]imidazol-2-yl)thio) acetic acid (1),which on cyclization with acetic anhydride and pyridine gives 7- methoxybenzo[4,5]imidazo[2,1-b]thiazol- 3(2H)-one(2), which on condensation with different aryl aldehydes in the presence of anhydrous sodium acetate in glacial acetic acid, furnishes a arylidene thiazolidinone. The purity of the synthesized compounds was confirmed by melting point and TLC.The structures were established by different spectral analysis such as FTIR,1HNMR, and CHN analysis. The newly synthesized compounds (3a-d) were in vivo evaluated f
... Show MoreHard-grade asphalt binders, such as AC 20–30, offer excellent resistance to permanent deformation but are inherently brittle, making them highly susceptible to fatigue and low-temperature cracking. While polymer modification addresses these issues, virgin polymers remain expensive. Despite the growing interest in recycled plastics, the rheological impact of complex waste streams, specifically polyvinyl chloride (PVC) derived from flex banners containing plasticizers, on excessively stiff binders within the complete Superpave Performance Grading (PG) framework remains critically underexplored. This study introduces a novel valorization approach by utilizing solvent-extracted flex banner waste (WPVC) as a dual-action modifier. It leverages
... Show MoreCarboxymethyl cellulose (CMC) is one of the important cellulose derivatives, and it can be developed as a host polymer for solid polymer electrolyte (SPE) membrane. This study aimed to synthesis of CMC from coconut fiber cellulose and it was applied to prepare the SPE membranes. Cellulose isolation was conducted through the delignification and bleaching process, while the CMC synthesis was conducted through alkalization and carboxymethylation treatments. SPE membranes were prepared by blending CMC with carboxymethyl chitosan (CMCh) (80/20) and mixed with various weight percentages of LiOAc at room temperature. SPE membranes characterizations were conducted using FTIR, EIS, XRD, SEM, and tensile testi