China
Africa
Explore chapters and articles related to this topic
Monodisperse Droplet Spray Drying
Published in Nan Fu, Jie Xiao, Meng Wai Woo, Xiao Dong Chen, Frontiers in Spray Drying, 2020
Nan Fu, Jie Xiao, Meng Wai Woo, Xiao Dong Chen
The key to the success of the technology of the monodisperse droplet spray dryer is the ability to prevent or minimize the blockages occurring within the nozzle itself. There are some designs for the atomizer that have long thin capillary sections that make the pressure drop rather large, and a fibre or a particulate “contamination” within the fluid conduit leading to the nozzle tip can cause the whole process to fail. Sometimes, an inline filter needs to be implemented, such as that trialled by Rogers (2011). In general, it is recommended that the feed fluid should be filtered with a “sieve” of appropriate aperture size to seclude the large obstacles. Homogenization has been also commonly used to ensure the homogeneity of the fluid for processing. The nozzles fabricated for use by the Auckland–Monash track, now produced reliably at Nantong Dong Concept New Material Ltd, China, were those that have a very “shallow” nozzle tip which inserts a small pressure drop. The conduit leading to the nozzle tip is a “fat” tube that does not insert very much pressure drop. In any case, producing nice uniform particles using the monodisperse droplet spray dryers requires skilled operations.
Pyrotechnic Principles
Published in John A. Conkling, Christopher J. Mocella, Chemistry of Pyrotechnics, 2019
John A. Conkling, Christopher J. Mocella
Varying degrees of homogeneity can be achieved by altering either the extent of mixing or the particle size of the various components (or both, for maximum effect). Striking differences in reactivity can result from changes in either of these, as Mr. Guthrie observed with his “fulminating powder.”
Reference Materials
Published in Piotr Konieczka, Jacek Namieśnik, Quality Assurance and Quality Control in the Analytical Chemical Laboratory, 2018
Piotr Konieczka, Jacek Namieśnik
Homogeneity: Condition of having a uniform structure or composition with respect to one or more specified properties. RM is said to be homogeneous with respect to a specified property if the property value, as determined by tests on samples of specified size, is found to lie within the specified uncertainty limits, the samples being taken either from different supply units (bottles, packages, etc.)—between-bottle homogeneity, or from a single supply unit—within-bottle homogeneity.
Development and characterization of jute/cotton reinforced epoxy/polyester hybrid-resin composite material
Published in Mechanics of Advanced Materials and Structures, 2023
Atta Ur Rehman Shah, Hammad Ahmad, Muhammad Hamza Abid, Saad Arif, Zarak Khan, Mushtaq Khan, Faramarz Djavanroodi
The first step is to prepare the EP resin in which 75% of part A is mixed with 25% of part B according to a mixing ratio of 3:1. The mixture is stirred well for 2 min to ensure homogeneity. The resulting compound is subjected to a dwell time of 15-20 min until the bubbles disappeared. The second step is to prepare the UP resin which started by pouring a few drops of cobalt accelerator into the UP resin. The mixture is stirred well for 2 min to ensure uniform dispersion of the accelerator. Both the EP and UP resins are prepared and ready for individual sample preparation and further procedures of hybrid resin formulation.
Study of mixing and discharging of dry particles in a truck mixer
Published in Particulate Science and Technology, 2020
Yuanqiang Tan, Rong Deng, Hao Zhang, Shengqiang Jiang
The mixing and discharging processes of binary particles in a mixer truck are experimentally tested and numerically simulated using DEM. The contact model and associated parameters in DEM are calibrated by several designed tests before adopting to the numerical simulations of truck mixer, and then validated by experiments in terms of the discharging time and the BPC of discharged samples. According to the experimental and numerical results, main conclusions can be summarized as follows:The BPC of 10 groups of discharged samples follows a law that it increases from Sample 1 to 5 and then decreases upto Sample 9 forming a parabola, finally increases to Sample 10.The discharging time is associated with the discharging speed and filling rate, but the influence of the mixing speed on it is slight. However, the discharging rate only depends on the discharging speed rather than the filling rate and mixing speed. The discharging speed of 8 rev/min produces the largest discharging rate, but its discharging homogeneity is the lowest amidst the three discharging speeds.The mixing homogeneity decreases with the increase of mixing time, mixing speed and filling rate when the mixture is uniform prior to the mixing. In this study, the mixing homogeneity is high when mixing speed is 1 rev/min and the filling rate is 40%.The discharging homogeneity decreases with the increase of mixing speed and filling rate as it is influenced by the mixing homogeneity. To obtain an appropriate discharging homogeneity, a mixing speed of 1 rev/min, a discharging speed of 5 rev/min and a filling rate of 40% may be chosen. But considering the discharging rate, higher filling rate and discharging speed are recommended.