Auriga crossbeam workstation

The TEM grid specimens were imaged and analyzed in a Hitachi SU6600 field emission scanning electron microscope (Hitachi, Tokyo, Japan) equipped with a Bruker energy-dispersive X-ray detector (Bruker Nano GmbH, Berlin, Germany) and a NORDIF electron backscatter (EBSD) detector (NORDIF, Trondheim, Norway). For elemental analysis of particles, an acceleration voltage of 15 keV, analytical working distance of 10 mm and electron probe current 7–8 nA were used. For aggregates/agglomerates with primary particle sizes less than 20 nm, an area of approximately 100 × 100 nm was scanned for X-ray acquisition in a particle–dense area to obtain elemental spectra. For larger particles (> 30 nm) X-ray spectrums from single particles were obtained. In addition, an Auriga Crossbeam Workstation (Carl Zeiss AG, Oberkochen, Germany), equipped with INCA X-Max silicon drift detector (Oxford Instruments, Abingdon, UK) for energy dispersive X-ray microanalysis was used.
The phase and elemental composition of the particles were studied by a Zeiss Libra 120 transmission electron microscope equipped with an OMEGA energy filter (Carl Zeiss AG, Oberkochen, Germany). Particle diameter measurements were conducted by statistical analysis of TEM images using the Minitab version 16 software (Minitab Statistical Software, Minitab 16; https://www.minitab.com).

SEM images were captured using an SEM-FIB Zeiss Auriga CrossBeam Workstation (Jena, Germany). Prior to image acquisition, all the samples were coated with a thin layer of iridium, ensuring a good electron outflow. Average fiber diameter and fiber angular distribution were evaluated from 100 and 50 measurements, respectively, performed in SEM images using the ImageJ 1.53 software (NIH, Bethesda, Rockville, MD, USA).

SEM observations were carried out using a Carl Zeiss AURIGA CrossBeam Workstation. Samples (filter paper with dry suspension) were placed on the SEM support using carbon conductive double-sided adhesive tape.

Airborne particles were sampled on polycarbonate filters in the workspace of the aluminum titanium master alloy smelting shop at VSMPO-AVISMA Corporation, Verkhnyaya Salda, Sverdlovsk Region, Russia, and analyzed for elemental composition by SEM-energy-dispersive spectroscopy using the Carl Zeiss AURIGA^® CrossBeam^® Workstation (Carl Zeiss NTS, Oberkochen, Germany). Table 5 demonstrates the prevalence of the following three elements in the average composition of the samples: titanium (17.5%); aluminum (14.8%); silicon (12.0%), represented by oxides of these metals.
Based on the above data, aqueous suspensions of TiO₂, SiO₂, and Al₂O₃ nanoparticles were specially prepared for the experiment by laser ablation of the surface of a superpurity metal plate under a layer of deionized water. The particles had spherical or near-spherical shape (see Figure 9 showing a scanning electron microscopy (SEM) image of Al₂O₃ particles as an example) and a symmetrical size distribution (Figure 10) with the mean (±s.d.) diameters of 27 ± 7 nm for TiO₂, 43 ± 11 nm for SiO₂, and 21 ± 6 nm for Al₂O₃.

For the investigation of the morphology of the samples, scanning electron microscopy (SEM) was used (Auriga CrossBeam Workstation, Carl Zeiss, Oberkochen, Germany). To examine the chemical structure of GO and rGO, X-ray photoelectron spectroscopy (XPS) was used (UHV Multichamber XPS, Prevac, Rogów, Poland). Analyses of the reduction efficiency and structural changes of the GO and rGO samples were performed using a Raman spectroscopy system (Renishaw Invia, Wotton-under-Edge, UK) at room temperature; the laser was excited at a wavelength of 532 nm and used at a power lower than 1 mW. The electronic properties of GO and rGO were measured using the Hallotron ECOPIA HMS 5500 system.
For SEM and Raman spectroscopy analysis, the graphene materials were deposited onto a Si substrate. For XPS measurements, powdered (freeze-dried) samples were used. For the electrical measurements, freeze-dried samples were pressed into a tablet form.

Planktonic-grown bacteria at OD₆₀₀ = 3–4 (1.5–2 × 10⁹ cfu/mL), gradient-collected EVs (0.5–1.5 × 10¹⁰ particles), and apoplastic fluids passed through 0.2 µm filters were used for SEM. The cells were chemically fixed using 2.5% glutaraldehyde in 50 mM cacodylate buffer (pH 7.0) containing 2 mM MgCl₂. Then, the cells were applied to a glass slide, covered with a cover slip, and plunged frozen in liquid nitrogen. After this, the cover slip was removed, and the cells were placed in a fixation buffer again. After washing four times with buffer, post-fixation was carried out with 1% OsO₄ for 15 minutes. Two additional washing steps with buffer were followed by three times washing with double distilled water. The samples were dehydrated in a graded acetone series, critical point dried, and mounted on an aluminium stub. To enhance conductivity, the samples were sputter coated with platinum. Microscopy was carried out using a Zeiss Auriga Crossbeam workstation at 2 kV (Zeiss, Oberkochen, Germany). The vesicle size was manually measured across five randomly selected SEM micrographs using Fiji software (74 (link)).

All the nanostructures’ characterization was performed with the synthesis product in powder form. In order to study the morphology and elemental composition of the nanostructures, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) inside an AURIGA CrossBeam workstation were performed (Zeiss, Oberkochen, Germany). The structural characterization was carried out by X-Ray diffraction (XRD) using X’Pert PRO MRD diffractometer (PANalytical, Royston, UK) with Cu Kα radiation and the data acquisition range was 10–90° (2θ) with a step size of 0.033°. Fourier-transform infrared (FTIR) spectra were acquired in the range of 4000–525 cm⁻¹ with 4 cm⁻¹ resolution and 45° incident angle. The data was recorded using a Smart iTR attenuated total reflectance (ATR) sampling accessory (Thermo Scientific, Waltham, MA, USA) equipped with a single bounce diamond crystal on a Thermo Nicolet 6700 Spectrometer (Thermo Scientific, Waltham, MA, USA). Raman spectra were acquired using an inVia Reflex micro-Raman spectrometer (Renishaw, Wotton-under-Edge, UK) equipped with an air-cooled CCD detector and a HeNe laser using a 532 nm laser excitation with a power of 50 mW, with 0.3 cm⁻¹ resolution. All measurements were obtained with an intensity of 50 µW at room temperature in a range of 100–1600 nm, using an integration time of 2 scans (10 s each).