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Mathematical Morphology
Published in Vipin Tyagi, Understanding Digital Image Processing, 2018
Granulometry is the name given to the determination of the size distribution of features within an image, particularly when they are predominantly circular in shape. Opening operations with structuring elements of increasing size can be used to construct a histogram of feature size, even when they overlap and are too cluttered to enable detection of individual features. The difference between the original image and its opening is calculated after each pass. At the end of the process, these differences are normalized and used to construct a histogram of feature-size distribution. The resulting histogram is called the pattern spectrum of the image.
Trialling one-part geopolymer production including iron ore tailings as fillers
Published in International Journal of Mining, Reclamation and Environment, 2022
Douglas B. Mazzinghy, Ricardo A.M. Figueiredo, Anita Parbhakar-Fox, Mohsen Yahyaei, James Vaughan, Malcolm S. Powell
Iron Ore Tailings (IOT) from a mine located in Minas Gerais state was used to produce one-part geopolymers for building materials applications in Brazil. Commercial sodium hydroxide (SH) NaOH in micro pearls (purity ≥ 97%) and commercial sodium silicate (SS) Na2SiO3 in solid form (SiO2/Na2O = 2.11 and 100% < 45 microns) were considered as activators. Commercial metakaolin (MK) Al2O3.2SiO2 was used as a precursor. The samples of IOT and MK were characterised as follows: i) particle size distribution was obtained by laser granulometry using CILAS 1190; ii) mineral phase was obtained by X-ray diffraction (XRD) using PANalytical X’Pert APD diffractometer with copper radiation (CuKα); and iii) the chemical composition was obtained by X-ray fluorescence (XRF) using Philips (PANalytical) spectrometer PW 2400. Figure 1 presents the particle size distribution for IOT and MK samples. The D80, D50 and D20 are 124.7 µm, 77.1 µm and 36.2 µm for IOT and 55.6 µm, 24.1 µm and 5.9 µm for MK. To further optimise, the IOT sample could have had its particle size distribution reduced (by grinding) to increase surface area and consequently increase the filler effect on the mortar.
Characterization and purification of waste phosphogypsum to make it suitable for use in the plaster and the cement industry
Published in Chemical Engineering Communications, 2020
Yassine Ennaciri, Ilham Zdah, Hanan El Alaoui-Belghiti, Mohammed Bettach
Physical and morphological characterizations were performed on PG and on the compounds produced in this work by the following techniques: X-ray diffraction (XRD BRUKER D8 with Cu Kα radiation) and scanning electron microscopy X-ray analysis (SEM Environmental FEI Quanta 200). The particle size distribution was determined by laser granulometry (CED center El Jadida). Concentrations of chemical elements were obtained by X-ray fluorescence (XRF S4 PIONEER BRUKER aXS), flame photometer (FP JENWAY 500-731 Model PFP7), and inductively coupled plasma mass-spectrometry (ICP-MS; HP-4500 instrument). Infrared spectra were performed by Fourier transform infrared spectroscopy (FTIR 8400 s SHIMADZU spectrometer) using KBr pellets in the region of 4000–450 cm−1. Raman spectrum was performed by Timegated Raman Spectrometer. The dehydration and carbonation degree of our samples were investigated by thermogravimetric analyses (DTG-60 type SHIMADZU).
Boosting the performance of low-carbon alkali activated slag with APEG PCEs: a comparison with ordinary Portland cement
Published in Journal of Sustainable Cement-Based Materials, 2023
Yue Zhang, Lei Lei, Johann Plank, Liugang Chen
The slag used in this research was provided by the Ecocem company in Fos sur mer, France. Its fineness was 4450 ± 250 cm2/g, which passed GGBFS Class A based on the concrete standard NF EN 206-1/CN (December 2012). Its oxide composition determined by X-ray fluorescence analysis (Axios, PANalytical, Almelo, the Netherlands) is shown in Table 1. The particle size distribution of slag was analyzed using laser granulometry, as depicted in Figure 1(a). The analysis yielded parameters of 10.72 µm and 30.99 µm for the average particle size (diameter at 50%) and the diameter at 90% cumulative distribution, respectively.