![]() When doing a grep on a huge file, it may be useful to see some lines after the match. Displaying lines before/after/around the match using grep -A, -B and -C $ grep -iw "is" demo_fileĪnd this is the last line. Please note that this output does not contain the line “This Line Has All Its First Character Of The Word With Upper Case”, even though “is” is there in the “This”, as the following is looking only for the word “is” and not for “this”. The following example is the WORD grep where it is searching only for the word “is”. When you search for “is”, without any option it will show out “is”, “his”, “this” and everything which has the substring “is”. The following example is the regular grep where it is searching for “is”. Just doing out a normal search will show out all the lines. If you want to search for a word, and to avoid it to match the substrings use -w option. Checking for full words, not for sub-strings using grep -w The preceding item is matched at least n times, but not more than m times.ĥ.+ The preceding item will be matched one or more times.* The preceding item will be matched zero or more times.? The preceding item is optional and matched at most once.$ grep "lines.*empty" demo_fileįrom documentation of grep: A regular expression may be followed by one of several repetition operators: i.e To search “linesempty” in the demo_file. In the following example, it searches for all the pattern that starts with “lines” and ends with “empty” with anything in-between. This is a very powerful feature, if you can use use regular expression effectively. Match regular expression in files Syntax: So it matches all the words such as “the”, “THE” and “The” case insensitively as shown below.Īnd this is the last line. This searches for the given string/pattern case insensitively. Case insensitive search using grep -i Syntax: $ cp demo_file demo_file1ĭemo_file:this line is the 1st lower case line in this file.ĭemo_file:Two lines above this line is empty.ĭemo_file1:this line is the 1st lower case line in this file.ĭemo_file1:Two lines above this line is empty.ĭemo_file1:And this is the last line. When the Linux shell sees the meta character, it does the expansion and gives all the files as input to grep. The grep output will also include the file name in front of the line that matched the specific pattern as shown below. For this example, let us copy the demo_file to demo_file1. This is also a basic usage of grep command. Checking for the given string in multiple files. ![]() The basic usage of grep command is to search for a specific string in the specified file as shown below. Search for the given string in a single file This Line Has All Its First Character Of The Word With Upper Case.Īnd this is the last line. This line is the 1st lower case line in this file. THIS LINE IS THE 1ST UPPER CASE LINE IN THIS FILE. ![]() In this article let us review 15 practical examples of Linux grep command that will be very useful to both newbies and experts.įirst create the following demo_file that will be used in the examples below to demonstrate grep command. Earlier we discussed 15 practical examples for Linux find command, Linux command line history and mysqladmin command. This is part of the on-going 15 Examples series, where 15 detailed examples will be provided for a specific command or functionality. You should get a grip on the Linux grep command. ![]()
0 Comments
![]() ![]() eBay is not affiliated with or endorsed by Canon. When you buy one of the products listed here, you effectively get instant access to a code that will allow you to activate your chosen subscription plan.Ĭontent provided for informational purposes only. After this time, you’ll have to buy a subscription plan to keep using the premium applications. This product can be downloaded directly from the official Microsoft Office website, and you can use it for free during the first month. Is there an office 365 download available? The only difference between these plans is the number of simultaneous users: your Office 365 Personal license only allows using the available services in a single computing device, while your Office 365 Home license can be effectively used with up to five different computing devices. These are essentially the exact same plans with the same available apps and the same available OneDrive storage of 1TB per user. Technically, you cant use a Microsoft Office personal plan for working in a business setting. Office 365 Home vs Personal – what’s the difference? ![]() ![]() Office 365 Business Premium: Includes the Office Online apps along with the classic offline versions for the same apps, as well as OneDrive for Business – a cloud-based solution for effective organizational file sharing.Office 365 Business: Includes only the Office Online apps, along with security solutions and device management features best suited for business operations encompassing up to 300 users.Office 365 Student: Includes the full Office Online suite (Word, Excel, PowerPoint, OneNote) along with unlimited cloud storage, and it can be used in up to five computers simultaneously available only to learning institutions.Office 365 Home: Includes the exact same features as the personal subscription, but it can be used in up to five computing devices at once.Office 365 Personal: Includes the most common Office applications, including Word, Excel and PowerPoint, as well as OneNote, Outlook, Publisher and Access.For example, here are five subscription plans catering to domestic users, students and small-to-medium business owners: There are several available Office 365 plans, each custom tailored to meet the specific requirements and match the budget of various demographics. Here you will find all the information you need to decide which plan is right for your particular situation. It’s available as a subscription service that provides full access to updated the versions of these productivity tools, and includes different plans meant for domestic users, office users and students. Microsoft 365 Personal - For Pc, Mac, Ios And Android, English Subscription, Middle East Version. Fast and free shipping free returns cash on delivery available on eligible purchase. Office 365 joinedthe ubiquitous Microsoft Office software suite in 2011. Buy Microsoft Office 365 Home Personal online on Amazon.ae at best prices. A Quick Guide to Microsoft Office 365 Subscription Plans ![]() ![]() ![]() 9 Proponents of CFR-PEEK hypothesize that it may help to avoid potential issues such as stress shielding and bone resorption, which are common problems experienced when stainless steel or titanium implants are used in total knee replacements. 9 It can also be manufactured to match the modulus of both cortical and cancellous bone densities. ![]() ![]() It has a modulus very similar to bone and an ability to withstand prolonged fatigue strain. CFR-PEEK is readily accepted by the body and does not break down over time. 9 More recently, CFR-PEEK has been used in orthopedic implants and may be ideal for articulating implants, including knee replacement products. 8Ĭarbon-fiber-reinforced polyetheretherketone (CFR-PEEK) has historically been used in spinal cages, bone fixation screws, and cardiac and neurological leads. As a result, new implants made of innovative materials are being introduced and evaluated with the goal of improving implant survival rates and reducing the associated burden of revision surgery. 6, 7 Consequently, a high percentage of patients are required to undergo a second knee replacement within 10 years of their initial surgery. 4, 5 Despite the improvement, the life span of the prosthesis is ultimately finite, as mechanical wear, aseptic loosening, infection, instability, and periprosthetic fractures are reasons for revision of knee arthroplasty. 1 – 3 For severe cases of knee OA, total knee replacements are the standard of care, as they relieve the patient’s pain so that they can return to their normal daily activities. For example, knee osteoarthritis (OA), a chronic degenerative joint disease, is very common among people over the age of 60 years. The ongoing development and improvement of orthopedic implants requires much attention as surgeries performed to treat traumatic injuries and joint diseases, along with their associated complications, are highly prevalent. Future studies should continue to investigate CFR-PEEK’s potential benefits. Nevertheless, available studies strongly support CFR-PEEK as a promising and suitable material for orthopedic implants because of its biocompatibility, material characteristics, and mechanical durability. There is limited literature available assessing the performance of CFR-PEEK, specifically as an implant material for arthroplasty systems. A total of 23 articles were included in this review. The search was also expanded by reviewing the reference sections of selected papers and references and benchmark reports provided by content experts. A comprehensive search in PubMed and EMBASE was conducted to identify articles relevant to the outcomes of CFR-PEEK orthopedic implants. The aim of this systematic review is to investigate the properties, technical data, and safety of CFR-PEEK biomaterial and to evaluate its potential for new innovation in the design of articulating medical devices. Carbon-fiber-reinforced polyetheretherketone (CFR-PEEK) has been successfully used in orthopedic implants. ![]() ![]() ![]() When viewing an image, you can tell if it is a Live Photo when it has the diffusing circle icon in the top left, along with the word "LIVE" next to it.Find the Live Photos that you want to create a video file with.It's insanely easy and lets you create amazing memories! Here's how to make a video from multiple Live Photos. The process is baked directly into iOS itself, so you don't need to import your Live Photos into an app like iMovie to do so. In iOS 13, Apple added the ability to stitch together multiple Live Photos (not necessary to have them back-to-back) to create a video clip. How to stitch together multiple Live Photos to create a video Images with the Long Exposure effect are still counted as Live Photos. You can change it back to a Live Photo at any time. ![]() When you change a Live Photo into a GIF with either the Loop or Bounce effect, it will go into your Animated album instead of Live Photos. If you are enjoying intoLive, please leave us reviews.Turn Live Photos to GIFs on IOS 15 by showing: Tap the Live indicator to bring up a menu, select your animated effect (Image credit: iMore) Auto-renewal will be disabled, but refunds will not be given for any unused portion of the subscription term. ![]() When canceling your subscription, the subscription will stay active until the end of the period. You can turn off auto-renewal from your Account Settings during your free trial. You can manage or cancel your subscription from your Account Settings after your purchase. Your subscription will renew automatically unless you turn off auto-renew at least 24 hours before the end of the current subscription period. Subscription fees will be charged to your iTunes account upon confirmation of purchase. Subscriptions are billed weekly, monthly, or annually depending on the subscription plan selected. With the intoLive subscription, you can have unlimited access to all features of intoLive. Customize live wallpapers using the live Photo Save video at 24, 30 or 60 FPS (Frames Per Second) Save video in SD, HD, FHD or 4K quality (Depending on the device model, 4K may not be supported.) Adjust brightness, contrast, saturation, warmth, and sharpness for color correction Apply artistic filters for cinematic effects Various frame designs, edit your video even more professionally Make an awesome slideshow with Clip Motion(Ken Burns effect) Volume control and mute for the original video Add music from your iTunes Library or upload your own music file 100+ different special royalty-free soundtracks Then, at the left bottom of your screen, click the share icon and select save as video from the list of alternatives. Choose all the Live Photos you wish to include in your video by clicking them all. Auto-save videos as drafts and resume editing anytimeĪdd Effects, TEXT and STICKERS with a few taps In the top right corner of the screen, press Select. Compatible with every media format available on iPhone Combine photos, videos, Live Photo, and GIFs Optimized editor to merge multiple video clips Share directly to TikTok, Instagram, YouTube and other social media Various canvas formats optimized for Social Media (TikTok, Reels, and Shorts) All you have to do is: Open the photos in the Photos app Click the blue Share icon Scroll down Click 'Save as Video' Once you've clicked 'Save as Video', your new video will appear in your Photo collection. Optimized Canvas Ratio for creating vertical Videos (9:16 aspect ratio) Method 1: iOS 13 Photos App If your iPhone is running iOS 13 or later, it's very easy to turn your live photo into a video. You can even create a video by combining several Live Photos to create a longer video. IntoLive offers various features for video editing ranging from basic to professional. Save Live Photo to Video with iOS Tools For users withiOS13 or later, you can finally save your Live Photos as videos on your iOS device. Tired of editing on such a small screen? Create eye-catching Social Media videos using intoLive, optimized for creating vertical videos (9:16 aspect ratio). Easy-to-use Video Editor for Creators! Create extraordinary videos for TikTok, Reels, and Shorts easily while using your creative ideas. ![]() ![]() The name was not among the thousands proposed, including rejected options such as Apache (the original name of the P-51 Mustang), Falcon (owned by Chrysler at the time), Eagle, Tropicale, Hawaiian, and Thunderbolt. After Henry Ford II returned from the Los Angeles Auto Show (Autorama) in 1953, he approved the final design concept to compete with the then new Corvette. Crusoe saw a painted clay model on May 18, 1953, which corresponded closely to the final car he gave the car the go-ahead in September after comparing it with current European trends. The concept was for a two-passenger open car, with a target weight of 2,525 lb (1,145 kg), a 252 cu in (4.1 L) Ford Y-block Interceptor V8 based on the forthcoming overhead-valve Ford engine slated for 1954 model year introduction, and a top speed over 100 mph (161 km/h). Hershey took the idea and began working on the vehicle. Walker promptly telephoned Ford's HQ in Dearborn and told designer Frank Hershey about the conversation with Crusoe. although if anything existed at the time beyond casual dream-car sketches by members of the design staff, records of it have never come to light. Walking in the Grand Palais in Paris, Crusoe pointed at a sports car and asked Walker, "Why can't we have something like that?" Some versions of the story claim that Walker replied by telling Crusoe, "Oh, we're working on it". Crusoe and Walker met in France in October 1951. Hershey's participation in the creation of the Thunderbird was more administrative than artistic. Boyer was the lead stylist on the original 1955 two-seater Thunderbird and also had input in the following series of Thunderbirds that included the 30th Anniversary Edition. The Thunderbird was similar in concept, but was more American in style, more luxurious, and less sport-oriented.Ĭredit for the development of the original Thunderbird is given to Lewis Crusoe, a former GM executive lured out of retirement by Henry Ford II George Walker, chief stylist and a Ford vice president Frank Hershey, chief stylist for the Ford Division Bill Boyer, designer for the Body Development Studio, who became the manager of the Thunderbird Studio in the spring of 1955 and Bill Burnett, chief engineer. The completed one-off generated interest at the time, but had meager power, European looks, and a correspondingly high cost, so it never proceeded to production. Development Ī smaller two-seater sports roadster was developed at the behest of Henry Ford II in 1953 called the Vega. Thunderbird production ended in 1997, then briefly resumed as a two-passenger, marketed from 2002 to 2005.įrom its introduction in 1955 to its final phaseout in 2005, Ford produced over 4.4 million Thunderbirds. ![]() Sales were good until the 1990s when large two-door coupes became unpopular. Succeeding generations became larger until the line was downsized in 1977, again in 1980, and once again in 1983. For 1958, the Thunderbird was redesigned with a second row of seats. Ford positioned the Thunderbird as an upscale model and it is credited in developing a new market segment, the personal luxury car. Unlike the Chevrolet Corvette, it was not marketed as a sports car. The Thunderbird entered production for the 1955 model year as a sporty two-seat convertible. Introduced as a two-seat convertible, the Thunderbird was offered variously as a four-seat hardtop coupe, four-seat convertible, five-seat convertible and hardtop, four-door pillared hardtop sedan, six-passenger hardtop coupe, and five-passenger pillared coupe, with the final generation designed again as a two-seat convertible.įord targeted the two-seat Thunderbird as an upscale model, but the 1958 model year design introduced a rear seat and arguably marked the expansion of a market segment eventually known as personal luxury cars, positioned to emphasize comfort and convenience over handling and high-speed performance. ![]() The Ford Thunderbird (colloquially called the T-Bird) is a personal luxury car manufactured and marketed by Ford from model years 1955-2005 (with a 1997-2002 hiatus), across 11 generations. Sports car (first and eleventh generations). ![]() ![]() As planets form around stars, they exert a gravitational influence on one another as they settle into their orbits. Many of these worlds are closer in size to the largest planets in our solar system, like Jupiter or Neptune, and orbit very close to their host stars.īut rogue planets are likely much smaller. “The combination of Roman’s wide view and sharp vision will allow us to study the objects it finds in more detail than we can do using only ground-based telescopes, which is a thrilling prospect.”Īstronomers have used a variety of techniques, telescopes and missions to detect more than 5,400 exoplanets, or planets outside of our solar system. “Roman will be sensitive to even lower-mass rogue planets since it will observe from space,” said Naoki Koshimoto, lead author of the other study and an assistant professor at Osaka University, in a statement. This illustration shows what the Nancy Grace Roman Space Telescope will look like in orbit. “It’s very exciting to use gravity to discover objects we could never hope to see directly.”īut opportunities to spot rogue planets using microlensing are incredibly rare, so a telescope like Roman will come in handy. “Microlensing is the only way we can find objects like low-mass free-floating planets and even primordial black holes,” said Takahiro Sumi, lead author of one of the studies and a professor at Osaka University, in a statement. Researchers can use the changes in light around the planet to measure the planet’s mass. But anything with mass can cause this light-warping lensing effect, revealing other celestial objects.įor instance, if a rogue planet is in alignment with a distant star, the light from that star will essentially bend around the planet, resulting in a magnifying effect. The foreground star acts as a lens, magnifying and brightening the background star for a matter of hours. As stars in our galaxy move, they can align with more distant stars. Microlensing is a technique astronomers use to study distant stars and search for exoplanets. “This is the first measurement of the number of rogue planets in the galaxy that is sensitive to planets less massive than Earth.” “We estimate that our galaxy is home to 20 times more rogue planets than stars - trillions of worlds wandering alone,” said David Bennett, coauthor of both studies and a senior research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, in a statement. The findings were made during a nine-year survey called Microlensing Observations in Astrophysics, carried out at New Zealand’s Mount John University Observatory. Two new studies, both set to publish in a future edition of The Astronomical Journal, point to the discovery of only the second known Earth-mass rogue planet and present evidence suggesting that rogue planets are six times more abundant than star-orbiting planets in our galaxy. It comes in both 32-bit and 64-bit downloads.This artist's illustration shows an ice-encrusted, Earth-mass rogue planet drifting through space by itself. Previous versions of the operating system shouldn't be a problem with Windows 8, Windows 7 and Windows Vista having been tested. It can run on a PC with Windows 11 or Windows 10. Is WD Discovery for Windows 10 or Windows 11? Download and installation of this PC software is free and 4.4.407 is the latest version last time we checked. WD Discovery is provided under a freeware license on Windows from drive utilities with no restrictions on usage. Update Manager: Keep connected devices up to date with the latest software updates. ![]() Security Scan: Scan the network for security threats.Scheduler: Automate tasks and manage schedules. ![]()
![]() ![]() The app can keep track of their time for them but users need to plan for when in the day they will choose to read. In order for students to meet their reading goals and hatch their reading companion pet, they need to plan for when they will be reading each day. Planning: Developing a systematic approach for setting and achieving goals. The vast selection of books also allows for the user to have a better chance of finding a book they want to focus on, thereby providing yet another boost for those who struggle with focus. The read-to-me option also includes high-lighting the word being read. In both cases, the book is read to the user, providing an additional audio cue to help them maintain their focus. ![]() With Epic!, users also get the added bonus of having audiobook and read-to-me options to help those who struggle with reading and focus. The focus required for a book depends on its length-some are short and require little focus, while longer ones may require focus to be sustained over the course of days. By selecting a book and paying attention to what is on the page, the user is choosing to ignore internal and external distractions. The fact that Epic! is an app makes it an even more effective tool for exercising focus. Educators can use this app for free.Įpic! helps kids practice and improve the following skills:įocus: Getting started and then maintaining attention and effort to tasks.Īny reading provides the opportunity to practice focus skills. Parents can try Epic for free for 30 days, after which the cost is $9.99 a month or $71.99 a year. They “hatch” the egg by making their reading goals. Each user also has the ability to choose a “pet” to read with them by choosing an egg from a bunch of random colors. These users can add books to their Favorites section and keep track of their own reading goals. Each user selects categories that they are interested in and then Epic! curates a list of titles they might like. Users are allowed up to four profiles, each customized to the age and preferences of the child creating it. Epic even has books that are exclusive to their site such as Cat Ninja, My Pet Slime, and Cinderella Rex. There are also read-to-me books, audiobooks, quizzes, and a variety of different types of videos. It includes fiction, non-fiction, STEM, biographies, graphic novels, and DIY among its genres. "Epic is incredibly valuable because it gives students exposure to books that they wouldn't get from a library or our classroom.Epic! is a subscription-based, digital library of 40,000 books (as of March of 2021) aimed at children 12 and under. "Get access to thousands of books on all subject matters" – “Epic strikes the perfect balance between educational and fun, and should allow parents to feel more confident about introducing the iPad into their children’s daily lives as a tool.” –TechCrunch Multilingual books and fun reading formats make reading accessible for every student.ĩ out of 10 Epic Educators would recommend us to colleagues.Ĭoming soon! Epic School Plus, a district-funded premium offering that gives educators and students 24/7 access to the full Epic library.Įpic has been featured on The TODAY Show, CNET and Refinery 29, as well as in The Wall Street Journal, Parents Magazine, USA Today, Forbes, and more. Help with Daily 20: Teachers can easily assign and share books, then track daily and weekly reading. Quizzes, Dictionary Lookup and Spotlight Words help build skills. Parent dashboard lets you see what they’re reading and follow along with their progress.ĩ5% of Epic parents say Epic helped improve their child’s reading skills.Įpic School is free for educators and students to use during the school day.ĮLA Tools: Filter titles by AR, DRA, F&P, grade level and more. Up to 4 child profiles, so each kid can enjoy a personalized reading experience. ![]() Spotlight Words and audio-enabled Dictionary Lookup teach vocabulary and pronunciation.Ī paid subscription beginning with a 7-day free trial. Multilingual: The majority of books on Epic are in English, but we also have Spanish-, French- and Chinese-language books to engage readers of different backgrounds and interests.įun rewards and learning tools: Reading Buddies, badges and quizzes keep them motivated to read and learn. Featuring talented voice actors, fun music and exciting sound effects that bring stories to life! You can even download books to read offline!īooks that read to them: In addition to our library of more traditional ebooks, we have a huge collection of Read-To-Me books and audiobooks. Epic is the world’s largest digital library for kids! Our fun, kid-safe, interactive reading app fuels curiosity and reading confidence by letting kids freely explore their interests with instant access to 40,000+ books, audiobooks, learning videos and more.Īnytime, anywhere: Access our library from any Apple device. ![]() ![]() The outstanding feature of our implementation is that it is very easy to use and simple to setup. The Bonjour-Browser in iNet scans the connected local network for Bonjour services, detecting any hardware that ist connected via the Bonjour protocol (for instance computer, router, printer, …) and any software running Bonjour services, e. Bonjour uses industry standard IP protocols to allow devices to automatically discover each other without the need to enter IP addresses or configure DNS servers. For your convenience we added a bookmark function to store often needed addresses.īonjour, also known as zero-configuration networking, enables automatic discovery of computers, devices, and services on IP networks. The ping section in iNet enables you to find out if an IP exists (if its ping service is enabled otherwise you will get no response :-)). Ping is a computer network tool used to test whether a particular host is reachable across an IP network or not. The technology used in iNet scans on a very low level, therefore one can even find machines that don't want to be found, for instance a Mac OS X computer running in stealth mode. (MAC and Vendor cannot be detected anymore since iOS 11) A classic portscan on the choosen device can also be performed. Find out the name, vendor and IP of the connected devices as well as the number of running Bonjour services on that particular device. For most Apple Computers the particular computer model can be seen. iNet discovers and distinguishes between windows and macintosh computers with different icons. a computer or router, along with their name, IP and vendor. INet shows the devices connected to your local network, e. In the current release of iNet we implemented the following features: Its very easy and user friendly design even allows the unexperienced user to get a profound and understandable overview of a network and the running services. INet provides you with information about networks your iPhone or iPod touch is connected to. And iNet never phones home, your data is absolutely private on your iPhone. With iNet you know exactly what's going on! This easy to use App outlines a computer network even to the unexperienced user. ![]() Which devices are connected to my network? Are they online? Which services do they provide? Does somebody use my wifi network without my knowledge? These and other questions answers iNet fast and simple. Find out about security risks and keep your network under control. ![]() ![]() ![]() Amazon Redshift doesn’t support VARCHAR data types larger than 64 KB, so we can’t store traditional LOBs on Amazon Redshift. VARCHAR is better if the strings include multi-byte characters. JSON uses UTF-8 encoded text strings, so JSON strings can only be stored as CHAR or VARCHAR data types.Redshift is not a good choice for storing large JSON data sets because, by storing disparate data in a single column, JSON does not leverage Amazon Redshift’s column store architecture.This actually increase execution time of JSON functions. Redshift checks for valid JSON text every time it execute any JSON function on JSON text field.Select channelgrouping, json_extract_path_text ( trafficsource, 'campaign', true ) As campaign from traffic Following shows contents of a file named customer.json The order of the elements in the JSON file does not matter (matching is done by name). To load a JSON document with the ‘auto’ option requires a template that exactly maps the JSON elements to the table column names. ![]() This is a mapping document that COPY will use to map and parse the JSON source data into the target. We can automatically COPY fields from the JSON file by specifying the ‘auto’ option, or we can specify a JSONPaths file. The COPY command loads data into Redshift tables from JSON data files in an S3 bucket or on a remote host accessed via SSH. If you have questions or would like to see Flexter in action you can request a demo. You can find out more on our product page. The whole conversion process is fully automated. You don’t have to write a single line of code. Flexter fully automates the conversion of JSON to a relational model on Redshift. This has other limitations which will also be covered in this post.Īnother option is Flexter, our data warehouse automation tool for JSON (and XML). We can load whole JSON documents into Redshift and transform and query them with the JSON-SQL functions offered in Redshift.We will cover them in detail in this post. There are some serious limitations to this approach. ![]() This requires us to pre-create the relational target data model and to manually map the JSON elements to the target table columns. ![]() ![]() Zarzycki,J (1982): Les Verres et l'état vitreux.Götze,W (2009): Complex Dynamics of glass forming liquids.This theory describes a slowing down of structural relaxation on cooling towards a critical temperature Tc, typically located 20% above Tg. The microscopic dynamics at low to moderate viscosities is addressed by a mode-coupling theory, developed by Wolfgang Götze and collaborators since the 1980s. More recently, the fragility has been quantitatively related to the details of the interatomic or intermolecular potential, and it has been shown that steeper interatomic potentials lead to more fragile liquids. Materials with a higher enthalpy of configuron formation compared with their enthalpy of motion have a higher Doremus fragility ratio, conversely melts with a relatively lower enthalpy of configuron formation have a lower fragility. Bond breaking modifies the properties of an amorphous material so that the higher the concentration of broken bonds termed configurons the lower the viscosity. Fragility is related to materials bond breaking processes caused by thermal fluctuations. Strong melts are those with (R D-1) < 1, whereas fragile melts are those with (R D-1) ≥ 1. The fragility of amorphous materials is numerically characterized by the Doremus’ fragility ratio R D=Q H/Q L. Amorphous materials are classified accordingly to the deviation from Arrhenius type behaviour of their viscosities as either strong when Q H-Q L
|
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |