Tecnai tf20 tem

X-ray diffraction was used to identify the composition of the freshly prepared catalysts. The gaseous products from the pyrolysis-reforming of the waste tyres were collected by a Tedlar™ gas sample bag, and further analysed by packed column gas chromatography (GC). Permanent gases which included H₂, CO, O₂, N₂ and CO₂ were analysed by a Varian 3380 GC/TCD with a 2 m long, 2 mm diameter and 60–80 mm mesh molecular sieve packed column. Hydrocarbons including C₁–C₄ were analysed by a Varian 3380 with a flame ionization detector with 80–100 mesh HayeSep column and nitrogen carrier gas. The gases are reported on a nitrogen-free basis.
Thermogravimetric analyser-temperature programmed oxidation (TGA-TPO) was used to analyse the reacted catalysts to investigate the types of carbon formed during the pyrolysis-catalytic/reforming of waste tyres. Raman spectroscopy was used to determine the degree of graphitization of the carbon productions. The results were obtained using a Renshaw Invia Raman spectrometer at a wavelength of 514 nm and Raman shifts between 100 and 3000 cm^-1. Scanning electron microscopy (SEM) and transmission microscopy (TEM) were used to observe the surface characteristics of the fresh and reacted catalysts to help determine the structure of the carbon deposition on the catalyst surface. The instruments used were a Hitachi SU8230 SEM and a FEI Tecnai TF20 TEM.

The negatively stained specimens were prepared using the previous method [79 (link)]. 0.01 mg/mL of the protein sample was used to applied onto a continuous carbon-coated copper grid. The specimen was imaged using a Philips CM12 transmission electron microscope (TEM) (80 keV) with a side-mounted CCD camera (Model 791, Gatan, Pleasanton, CA, USA) or a FEI Tecnai TF20 TEM with a CCD camera.
For imaging the Walker A mutants, the specimens were imaged under a FEI Tecnai TF20 TEM, recording at a pixel size of 1.04 Å/pixel at the specimen level. 153 and 144 electron images were collected for p97^R155H-K251R and p97^R155H-K524R, respectively, and imported into Relion (version 3.1-beta-commit-ca101f) [80 (link)] for image processing. 23,342 and 23,020 particles of p97^R155H-K251R and p97^R155H-K524R were manually selected from the electron images, respectively, and the two-dimensional (2D) class averages with an assigned k of 50 were calculated. For the p97^R155H-K251R dataset, the numbers of side views for dodecamer and hexamer were 2173 and 313, respectively. For the p97^R155H-K524R dataset, the numbers are 2007 and 300, respectively.

LHNPs were synthesized according to our recently published procedures with minor modifications^{36 (link)}. Briefly, RNP was formed by complexing Cas9 protein with candidate sgRNA that was synthesized at Synthego with chemical modifications, mixed with PEI-adamantine (AD) and PEI-CD, and encapsulated into liposomes consisting of 1,2-dioleoyl-3-trimethylammonium-propane chloride salt (DOTAP, Avanti Polar Lipids), cholesterol (Avanti Polar Lipids), and DSPE-PEG₂₀₀₀-MAL (Avanti Polar Lipids) through extrusion. Morphology of LHNPs was determined using a TEM microscope (FEI Tecnai TF20 TEM).

EM imaging of DNA-nanogold conjugates and LDL-CETP mixtures were conducted using a Zeiss Libra 120 transmission electron microscope (Carl Zeiss SMT GmbH, Oberkochen, Germany). The TEM was operated at 120 kV. A single-axis tilt series of the DNA-nanogold was collected from −60° to +60° in steps of 1.5° at a nominal magnification of 125 k × (0.94 Å/pixel). The LDL-CETP cryo-ET tilt series were collected from −57° to +57° in steps of 1.5° at a nominal magnification of 50 k × (2.4 Å/pixel). The tilt series were acquired at ~1 μm defocus using a 4 k × 4 k Gatan UltraScan 4000 CCD camera. For the cryo-ET, the electron dose per tilt series was within ~25 e⁻/Ų. Low-dose data acquisition was conducted by using the TEM tomography software (Gatan Inc., Pleasanton, CA, USA) in Advanced Tomography mode.
EM imaging of DNA origami was conducted using a FEI Tecnai TF20 TEM operated at 200 kV. A single-axis tilt series of the DNA origami was collected from −48° to +48° in steps of 1.5° at a nominal magnification of 19 k × (1.85 Å/pixel). The tilt series were acquired at ~1 μm defocus using a Gatan K2 Summit direct electron detector, and the total electron dose was ~50 e⁻/Ų.

Transmission electron microscopy (TEM) analysis was performed with a FEI Tecnai TF20 TEM instrument at an accelerating voltage of 200 kV. Samples were prepared by evaporating a drop of dilute GNR solutions in chloroform onto carbon-coated copper TEM grids (400 mesh, TED PELLA, Inc.), which were allowed to dry for 24 h prior to imaging. Freeze-fracture TEM (FF-TEM) images were obtained either on a FEI Tecnai TF30 ST TEM instrument at an accelerating voltage of 300 kV or a JEOL JEM-100S at 100 kV. The FF-TEM samples, replicas of fractured surfaces of the LC-GNR composites, were prepared following a procedure described elsewhere^{51 (link)}. UV-Vis absorption and solution circular dichroism (CD) spectropolarimetry measurements were done using an OLIS spectrophotometer (1 cm path length quartz cuvettes). ¹H NMR spectra were recorded in CDCl₃ on a Bruker DMX 400 MHz spectrometer and referenced internally to residual solvent peaks at 7.26 ppm. Polarized optical microscopy (POM) observations of the induced chiral nematic liquid crystals (N*-LCs) were recorded and photographed using an Olympus BX-53 polarizing microscope equipped with a Linkam LTS420E heating/cooling stage. Differential scanning calorimetry (DSC) was performed using a Pyris 1 DSC instrument (Perkin Elmer). Thermogravimetric analysis (TGA) was performed using a TGA Q500 (TA Instruments).