8 results about "Field emission scanning electron microscopy" patented technology

This application relates to the field of field emission scanning electron microscopy (FET) technology, and in particular to an electron microscope gun valve. The electron microscope gun valve includes a valve seat and a second control valve disposed on the valve seat. The valve seat is sealed between the gun lens and the objective lens; the valve seat has a gas passage, including a first channel connecting to a molecular pump, a second channel connecting to an ion pump, and a third channel connecting to the gun lens, all three being interconnected. The second control valve can close the first channel to cut off its connection with the other two channels. Therefore, with the electron microscope gun valve of this application, which includes a gas passage and a second control valve, the molecular pump can be used to evacuate the microscope barrel and the ion pump first, allowing the ion pump to quickly reach the starting conditions before starting, thus avoiding forced start-up of the ion pump before the starting conditions are met, which would affect its service life, and effectively improving the efficiency of vacuum establishment in the microscope barrel.

A system for the fabrication of ε-phase MnAl / Co bilayer thin films, consisting of: a) a high-frequency magnetron sputtering system for the deposition of multilayer thin films on a silicon substrate, the sputtering system comprising: • a system for maintaining base pressure, configured to maintain a constant pressure; • three 2-inch targets consisting of MnAl, Co and Ta; and • a substrate rotation mechanism configured to rotate the substrate at a constant number of revolutions per minute; b) a layer deposition unit that is operationally connected to the RF magnetron sputtering system and enables the sputtering system to deposit layers sequentially: • a 3 nm thick Ta buffer layer on the silicon substrate; • a 60 nm thick MnAl layer on the Ta buffer layer; • a Co layer with a thickness of 1 nm to 5 nm on the MnAl layer; and • a 5 nm thick Ta top layer on the Co layer; c) an annealing furnace configured to anneal the deposited Ta and MnAl layers for 2 hours at 600 °C before the Co layer is deposited; and d) a characterization unit for analyzing the produced thin films, wherein the characterization unit comprises the following: • an X-ray diffraction (XRD) system for structural characterization; • an optical 3D profilometer for measuring surface structure and mean roughness; and • a field emission scanning electron microscope (FESEM) with energy-dispersive X-ray spectrometer (EDS) for analyzing surface morphology and elemental composition.

This invention relates to the field of materials analysis technology, specifically to a method for analyzing and identifying shale thin sections using a combination of optical microscopy and field emission scanning electron microscopy. First, from an optical perspective, the method combines the brightness distribution of bright-field images of shale thin sections with the birefringence deviation of cross-polarized images to determine mineral discrimination indices representing atomic number proxies. Then, based on the distribution of the mineral discrimination indices and the surface undulations of the shale thin sections, different biases are applied, and the positional bias vector is determined by combining this with the gray-level gradient distribution. Finally, based on the physical distance scale of the image and the pixel coordinate transformation process involving rotation and translation, the positional bias vector is used to determine the electron microscope stage coordinates corresponding to each pixel point for more accurate cross-scale positioning. This improves the accuracy of cross-scale positioning using optical microscopy and field emission scanning electron microscopy, significantly enhancing the reliability of shale thin section analysis and identification.

The present invention relates to the process for preparation of high-grade turbostratic graphene from subbituminous tertiary coal from North eastern region of India by ultrasonic-assisted chemical oxidation and ultrafiltration followed by thermal reduction process. More particularly, the present invention relates to the efficient, scalable, low-cost process for preparation of high-quality graphene by ultrasonication supported chemical oxidation, ultrafiltration followed by thermal reduction process from low-grade subbituminous Indian coals. The synthesis of coal-derived graphene material is confirmed by various analytical methods such as High-Resolution Transmission Electron Microscope (HRTEM), Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared (FTIR) spectroscopy. This process can produce graphene on a large scale without using harsh acids, making it safer and more eco-friendly than existing methods. The present invention offers a sustainable and effective way to produce graphene with potential applications in different domains.

The present disclosure provides a particle size statistical method of granular minerals of shale, comprising: collecting shale samples; cutting the collected samples into the size of 1 cm×1 cm×1 cm; performing argon ion polishing; magnifying the samples by the field emission scanning electron microscopy, collecting 500-1000 images; using Adobe Photoshop to seamlessly splice the collected images; using ImageJ in combination with EDS energy spectrum to determine types of mineral particles, performing background subtraction, and setting a reasonable grayscale threshold to classify the particle minerals; performing binary processing on the images of selected mineral particle types; identifying edges of granular minerals, and using a Analyze Particles command to statistically analyze and measure particle sizes, and drawing a particle size distribution histogram. The method can perform precise measurement and statistics on the particle sizes of shale particle minerals, and can perform full-scale statistical analysis on the distribution of different mineral particle sizes in the shale.

This invention discloses a morphology-based method and system for classifying pores in tight reservoir porous media, comprising: acquiring microstructural images of rock tight reservoir samples using field emission scanning electron microscopy; labeling the SEM images with two types of samples, pores and matrix / background, as training sets, and training a segmentation model for rock samples; segmenting the sample SEM images using the trained segmentation model to generate binary images that identify the background and pores; automatically measuring pore morphology parameters based on the binary images to obtain pore roundness and aspect ratio; classifying pore shapes according to preset quantitative classification thresholds for pore roundness and aspect ratio, and outputting statistical classification results; this invention achieves a systematic and objective characterization of pore cross-sectional shape, transforming the traditional subjective judgment-dependent pore morphology description into a quantifiable and comparable structural index, solving the problem that traditional pore morphology classification relies on subjective judgment and lacks unified quantitative standards.

In one aspect, cutting tools are described herein comprising wear resistant coatings employing one or more refractory layers of polycrystalline α-Al2O3. Briefly, a coated cutting tool described herein comprises a substrate, and a coating adhered to the substrate, the coating comprising a layer of polycrystalline α-Al2O3 deposited by chemical vapor deposition (CVD), wherein at least 5% of all grain boundaries in the polycrystalline α-Al2O3 layer have a misorientation angle less than 15 degrees as determined using a field-emission scanning electron microscope (FESEM) and an electron backscatter diffraction (EBSD) detector.

The application discloses a field emission scanning electron microscope, which comprises a source-beam-angle-of-field control mirror, an objective lens, an image-beam-angle-of-field control mirror arranged between the source-beam-angle-of-field control mirror and the objective lens, and an aperture arranged between the source-beam-angle-of-field control mirror and the image-beam-angle-of-field control mirror, wherein the source-beam-angle-of-field control mirror is provided with a first pole piece, the image-beam-angle-of-field control mirror is provided with a second pole piece, and the objective lens is provided with a third pole piece; and a centering coil is arranged between at least one of the first pole piece and the aperture, the aperture and the second pole piece, and the second pole piece and the third pole piece. According to the field emission scanning electron microscope, the beam current can be adjusted and the beam angle can be optimized, the degree of freedom of the electron beam adjustment is effectively improved, and the centering effect of the electron beam and the magnetic lens is improved.