Mastersizer 2000 particle size analyzer

The main properties of the soil are summarized in Table 1. The soil density (ρb) was measured from soil dry weight/isometric water weight, and the porosity was calculated as (1-ρb/2.65) × 100% [15 ]. The pH was determined in a mixture with distilled water to soil mixture of 5:1 (v/w) [5 (link)]. The soluble salt content was extracted as described in a previous report [16 (link)]. In brief, 10 g of soil was mixed with 50 mL of CO₂-free water and shaken 3 min. 20 mL of supernatant was evaporated at 105 °C and then H₂O₂ (10% of mass fraction) was used to remove organic matter. In order to make a comparison with EC measured using the conventional method, ECs of soil were evaluated with soil to distilled water ratios (v/w) of 1:2.5, 1:5 and 1:10 using a EC meter (SFENGCI, DDS-11A, Shanghai, China) [3 (link),4 (link)]. The soil particle size distribution was obtained by using Mastersizer2000particle size analyzer (Malvern Instruments Ltd., Malvern, UK).

The samples were degassed at 393 K for 1 h to obtain a residual pressure of less than 10⁻³ Torr. The amount of N₂ adsorbed at a relative pressure of P/P0 = 0.99 was used to determine the total pore volume. The morphology of bare and ligand bonded silica particles was examined with scanning electron microscope (Hitachi High Technologies, Tokyo, Japan). The dried samples (bare silica and ligand bonded silica particles) were put on aluminum stubs using adhesive carbon tape. A Q150T sputter coater was used to coat gold over the sample and 5 nm Au layer was deposited over the sample. This enhances the efficiency of the process using low voltages and giving a fine-grain, cool sputtering. A Thermo Electron (Waltham, MA, USA) Flash EA1112 elemental analyzer was used to carry out elemental analysis. A Malvern (Worcestershire, UK) Mastersizer 2000 particle size analyzer was used to get particle size distribution. Bare silica particles and ligand bonded silica particles (5 mg each) were dispersed in 5 mL isopropyl alcohol, sonicate for 10 min, vortexes for 5 min, and subjected to the optical bench of Mastersizer. Thermo gravimetric analysis were carried out over a temperature range of 30 to 800 °C at 5 °C per minute.

Particle size analysis of the film-forming solutions as a granulometric distribution of solid particles in water was performed in three repetitions using a Mastersizer 2000 particle size analyzer (Malvern Instruments, Worcestershire, UK). Characteristic parameters of the distribution, such as DV₁₀, DV₅₀, and DV₉₀ diameters corresponding to 10%, 50,% and 90%, respectively, of the volume (mass) of the set of particles were determined. The equivalent diameters D_3.2 and D_4.3 were calculated according to the equations: $$D_{3.2}=\frac{\sum d^3}{\sum d^2}$$
$$D_{4.3}=\frac{\sum d^4}{\sum d^3}$$
where d—diameter of a single solid particle, (µm).
Equivalent diameter D_3.2 defines the diameter of a sphere equivalent in area, whereas equivalent diameter D_4.3 defines the diameter of a sphere equivalent in volume or mass.

We chose representative samples in the Yili River Valley in May 2015, associated with regional DEM, land use types, climate, soil and other natural conditions. The self-made sampler (10 cm diameter and 50 cm height) was used to collect topsoil samples (0–20 cm). Each sample point was positioned by GPS, and factors such as latitude, longitude and elevation were recorded. One hundred twenty-seven topsoil samples at depths of 0–20 cm were collected (Fig. 1) including cultivated land samples (nine), garden samples (18), woodland samples (12), and grassland samples (88). The organic carbon concentration of the soil (g•kg⁻¹) was determined using the K₂Cr₂O₇-external heating method; total nitrogen concentration (g•kg⁻¹) was determined using the perchloric acid-sulphuric acid digestion method; total phosphorus in the soil was found using the acid-soluble and molybdenum antimony ratio colorimetric method; total potassium in the soil was determined using the acid digestion and flame photometric method; soil pH was determined using the potential method; SBD was determined using the ring shear testing method; water content was determined using oven drying method (Liu et al., 2016 (link)); and the Mastersizer 2000 particle size analyzer (Malvern Instruments, Malvern, England) was used to measure soil particle composition (Zhang et al., 2016 (link)).