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The present study proposes a new design of mechanical filter to suit the recirculating aquaculture system (RAS) as a high-efficiency alternative filter to the conventional swirl separator (CSS). The new filter is considered the developed version of CSS; thus, it is called thereafter as the swirl-vertical drum filter (SVDF) which is provided with a rotating vertical micro-screen drum equipped with a fixed vertical brush as a self-cleaning tool instead of the conventional backwash system. The performance of SVDF was evaluated under different drum rotational speeds, and drum rotation times using sinking and floating fish feed pellets and magnetic field device, and then, it was compared to CSS in terms of water quality and filtration efficiency under the same operational conditions. Experimental results showed better values of water quality including Dissolved oxygen (DO), pH and unionized ammonia (NH3). Also, the lowest value of COD was found to be 18.33 mg/L by using SVDF with floating feed pellets, whilst the highest value of 100.73 mg/L was found in the case of using the CSS with sinking pellets. Meanwhile, the magnetic field device had no effect on the filtration process. The lowest surface area of the vertical micro-screen drum of 0.217 ± 0.013 m2 was obtained at the drum's rotational speed of 20 rpm (0.39 m/s), rotation time of 150 min with floating feed pellets. Experimentally, it is found that the new SVDF has higher filtration efficiency than the CSS by about 57.57% under the same operational conditions. [ABSTRACT FROM AUTHOR]

The choice of design and operational parameters of vortex dust collectors (VDC) influences energy costs for ensuring the required dust collection efficiency at a given volumetric cleaned gas productivity. Data on the most expedient VDC design parameters are presented. Based on analytical relationships and computer simulation data, a method for calculating hydraulic resistance of the newly designed VDC and its separating capacity has been developed. [ABSTRACT FROM AUTHOR]

The results of experimental studies of hydraulic resistance, heat and mass transfer characteristics of a prismatic lattice polymer regular packing for various options of its installation in space are presented. Based on the conducted experimental studies, the most rational design of packing installation was determined (taking into account the decrease in hydraulic resistance and the increase in the efficiency of heat and mass transfer processes), for which the geometric characteristics are given and empirical dependences are obtained, which make it possible to determine the value of the hydraulic resistance of the dry and irrigated packing, the values of the volumetric coefficients of mass transfer and heat transfer. The results of the study can be used in enterprises where different types of cooling towers or devices for conducting heat and (or) mass transfer processes, such as absorption, are used, as well as in the development of packed scrubbers. [ABSTRACT FROM AUTHOR]

Purpose: The objectives of this study were to determine the radiological outcome of a new personalized total knee arthroplasty (TKA) design and also to analyze the radiological reproducibility of the surgical technique.Patients and Methods: A total of 100 consecutive TKAs performed in 99 patients using Persona knee system were recruited. Weight-bearing standing anteroposterior and lateral radiographs were done in all the patients, both pre-operatively as well as post-operatively, and various radiological parameters were analyzed and compared.Results: The full correction of the limb mechanical axis was achieved in 97% of patients, and the radiological parameters of coronal and sagittal alignment of femoral and tibial components showed good results. There were no substantial differences between the mean pre-operative and post-operative patellar height indices, and data were in the normal range. Posterior condylar offset (PCO) and posterior condylar offset ratio (PCOR) had increased as expected after TKA. The coverage of tibia was optimal with data in the normal range.Conclusions: Radiological assessment of the new personalized knee system design showed excellent results with various parameters restored to the normal values. Therefore, the prosthesis can be considered anatomic, and the surgical technique is reproducible allowing the prosthesis to be implanted easily and with high precision. [ABSTRACT FROM AUTHOR]