Backscattered electrons (BSE) consist of high-energy electrons originating in the electron beam, that are reflected or back-scattered out of the specimen interaction volume by elastic scattering interactions with specimen atoms. Since heavy elements (high atomic number) backscatter electrons more strongly than light elements (low atomic number), and thus appear brighter in the image, BSEs are used to detect contrast between areas with different chemical compositions. The Everhart-Thornley detector, which is normally positioned to one side of the specimen, is inefficient for the detection of backscattered electrons because few such electrons are emitted in the solid angle subtended by the detector, and because the positively biased detection grid has little ability to attract the higher energy BSE. Dedicated backscattered electron detectors are positioned above the sample in a "doughnut" type arrangement, concentric with the electron beam, maximizing the solid angle of collection. BSE detectors are usually either of scintillator or of semiconductor types. When all parts of the detector are used to collect electrons symmetrically about the beam, atomic number contrast is produced. However, strong topographic contrast is produced by collecting back-scattered electrons from one side above the specimen using an asymmetrical, directional BSE detector; the resulting contrast appears as illumination of the topography from that side. Semiconductor detectors can be made in radial segments that can be switched in or out to control the type of contrast produced and its directionality.
Search results are presented in an ordered list, and the higher up on that list a site can get, the more traffic the site will tend to receive. For example, for a typical search query, the number one result will receive 40-60% of the total traffic for that query, with the number two and three results receiving significantly less traffic. Only 2-3% of users click beyond the first page of search results. http://www.youtube.com/v/e29F5n3ea0I&feature=kp
The process of optimizing a website – as well as all the content on that website – so it will appear in prominent positions in the organic results of search engines. SEO requires an understanding of how search engines work, what people search for, and why and how people search. Successful SEO makes a site appealing to users and search engines. It is a combination of technical and marketing.
Before launching any marketing campaign, it’s important to determine your primary video goal. This could be to increase brand awareness, engagement, or even conversions for a free trial. It’s crucial to pick out just one or two goals for each video. When you define more than that, your video will seem unfocused, making it difficult for viewers to determine what they should do next.
SEM is not a camera and the detector is not continuously image-forming like a CCD array or film. Unlike in an optical system, the resolution is not limited by the diffraction limit, fineness of lenses or mirrors or detector array resolution. The focusing optics can be large and coarse, and the SE detector is fist-sized and simply detects current. Instead, the spatial resolution of the SEM depends on the size of the electron spot, which in turn depends on both the wavelength of the electrons and the electron-optical system that produces the scanning beam. The resolution is also limited by the size of the interaction volume, the volume of specimen material that interacts with the electron beam. The spot size and the interaction volume are both large compared to the distances between atoms, so the resolution of the SEM is not high enough to image individual atoms, as is possible with transmission electron microscope (TEM). The SEM has compensating advantages, though, including the ability to image a comparatively large area of the specimen; the ability to image bulk materials (not just thin films or foils); and the variety of analytical modes available for measuring the composition and properties of the specimen. Depending on the instrument, the resolution can fall somewhere between less than 1 nm and 20 nm. As of 2009, The world's highest resolution conventional (≤30 kV) SEM can reach a point resolution of 0.4 nm using a secondary electron detector. https://youtube.com/watch?v=e29F5n3ea0I&app=desktop
After your site has been built out, creating a social media presence is the best second step for most businesses. All businesses should have a Facebook Page that’s fully fleshed out with plenty of information about your business. Depending on your audience, you can also start a Twitter, Instagram, and/or Pinterest account. Social media is a long-term commitment that requires frequently updating and monitoring, but it’s one of the best ways to build an online community around your business.
As practice, try telling a story with your b-roll and planning out a shot sequence. For example, your subject might open a door from the hallway, walk into their office space, sit down at their desk, open their laptop, and begin typing. Seems simple, right? But a shot sequence showing this 10 second scenario might consist of six or more different b-roll clips.
Look at your short- and long-term goals to choose whether to focus on organic or paid search (or both). It takes time to improve your organic search rankings, but you can launch a paid search campaign tomorrow. However, there are other considerations: the amount of traffic you need, your budget, and your marketing objectives. Once you’ve reviewed the pros and cons, you can select the search strategy that’s right for you. http://youtu.be/7bNPg8UbhaE