Gaslift reactors are employed in several bioapplications due to their characteristics of cost-effectiveness and high efficiency. However, the nutrient and thermal gradient is one of the obstacles that stand in the way of its widespread use in biological applications. The diagnosis, analysis, and tracking of fluid paths in external draft tube gaslift bioreactor-type are the main topics of the current study. Several parameters were considered to assess the mixing efficiency such as downcomer-to-rizer diameter ratio (Ded/Dr), the position of the diffuser to the height of bioreactor ratio (Pd/Lr), and gas bubble size (Db). The multiple regression of liquid velocity indicates the optimal setting: Ded/Dr is (0.5), Pd/Lr is (0.02), and Db is (400) um. However, for technical and operational reasons, it was necessary to make some changes in the optimal values obtained from the numerical equations. The study also revealed that the size of gas bubbles is the characteristic that has the greatest influence on the dynamic efficiency of the fluid inside the bioreactor, since, reducing the bubble size by half can enhance the improvement rate in the circulation of the liquid up to 35%.
Abstract : Tin oxide SnO2 films were prepared by atmospheric chemical vapor deposition (APCVD) technique. Our study focus on prepare SnO2 films by using capillary tube as deposition nozzle and the effect of these tubes on the structural properties and optical properties of the prepared samples. X-ray diffraction (XRD) was employed to find the crystallite size. (XRD) studies show that the structure of a thin films changes from polycrystalline to amorphous by increasing the number of capillary tubes used in sample preparation. Maximum transmission can be measured is (95%) at three capillary tube. (AFM) where use to analyze the morphology of the tin oxides surface. Roughness and average grain size for different number of capillary tubes have b
... Show MoreCooperation spectrum sensing in cognitive radio networks has an analogy to a distributed decision in wireless sensor networks, where each sensor make local decision and those decision result are reported to a fusion center to give the final decision according to some fusion rules. In this paper the performance of cooperative spectrum sensing examines using new optimization strategy to find optimal weight and threshold curves that enables each secondary user senses the spectrum environment independently according to a floating threshold with respect to his local environment. Our proposed approach depends on proving the convexity of the famous optimization problem in cooperative spectrum sensing that stated maximizing the probability of detec
... Show MoreThe subgrade soil is the foundation plate form of the roadway; it should sustain its structural characteristics throughout the design life of the roadway with minimal requirements for maintenance. When Gypseous soil is implemented in the construction of subgrade, problems regarding collapsibility and poor structural capacity usually occur when the subgrade came in touch with excess water. Asphalt stabilization could furnish a proper solution to such problems. In this investigation, an attempt has been made to monitor the variations in compressibility characteristics of asphalt stabilized subgrade soil subjected to 30 cycles of (freezing-thawing) and (heating-cooling). Data have been observed after each 10 cycles, and compared with that of r
... Show MoreA one-dimensional hydraulic model was conducted to simulate the flow in Diyala River. The research aims to study the flow capacity along Diyala River and especially concerning on reach of the river within Baqubah City during flood seasons by using HEC-RAS, 5.07 software. Moreover, specifying the hydraulic problems and then the necessary treatments to overcome them were suggested. A 190 km length of the reach of Diyala River was included in this study, starts from Diyala submerged weir to the confluence of Diyala-Tigris River south of Baghdad City. Good agreement resulted between the measured and the simulation results with a determination coefficient (R2) value of 0.84 with Manning Co
Dialogue is one of the pillars of character building in the television series, through which it is possible to identify the most important characteristics and traits of the personality, in addition to its ability to reveal the most important problems at all levels. The following: (How does dialogue contribute to enhancing the traits of the alienated personality?). It therefore aims to identify the effectiveness of the dramatic dialogue in enhancing the traits of the alienated personality represented by (powerlessness, isolation, meaninglessness, objectification, non-standardization and rebellion). (The traits of the alienated character, and the second is the psychological function of the dramatic dialogue), to extract from them the main
... Show MoreDrilling solutions can be considered as an intricate mixture comprising of number of chemical additives which aid specific needs such as controlling the rheological properties and reducing corrosion. Inhibitors are substances that are added in small concentrations to corrosive environment to decrease the corrosion. Their applications can be found in drilling equipments. The effect of adding Zinc Sulphate and Carboxymethyl Cellulose to study their influence on the corrosion of carbon steel in Bentonite mud has been evaluated using Weight Loss Technique. This study focuses on determining rheological properties and corrosion characteristics. Results show CMC and ZnSO4 work as inhibitors when added to the Bentonite with inhibition
... Show MoreA novel median filter based on crow optimization algorithms (OMF) is suggested to reduce the random salt and pepper noise and improve the quality of the RGB-colored and gray images. The fundamental idea of the approach is that first, the crow optimization algorithm detects noise pixels, and that replacing them with an optimum median value depending on a criterion of maximization fitness function. Finally, the standard measure peak signal-to-noise ratio (PSNR), Structural Similarity, absolute square error and mean square error have been used to test the performance of suggested filters (original and improved median filter) used to removed noise from images. It achieves the simulation based on MATLAB R2019b and the resul
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