![]() This is the magic that happens when science and technology are combined. These calculations which took a lot of effort to solve are today carried out in the blink of an eye. When we consider the behavior of gases in Unit 5, we can use the data to calculate the molecular weight of each gas.Nowadays, different online calculators are available online to carry out stoichiometric calculations. Follow along and record the measurements to get the relative masses. Steve Boon shows how Avogadro's hypothesis can be used to measure the molecular masses of He, N 2 and CO2. ![]() The important point is that 1 mol of carbon-or of anything else, whether atoms, compact discs, or houses-always has the same number of objects: 6.022 × 10 23. The definition of a mole-that is, the decision to base it on 12 g of carbon-12-is arbitrary but one arrived at after some discussion between chemists and physicists debating about whether to use naturally occurring carbon, a mixture of C-12 and C-13, or hydrogen. Avogadro's number is the fundamental constant that is least accurately determined. A mole of C-12 by definition weighs exactly 12 g and Avogadro's number is determined by counting the number of atoms. The numerical value of Avogadro's number, usually written as No, is a consequence of the arbitrary value of one kilogram, a block of Pt-Ir metal called the International Prototype Kilogram, and the choice of reference for the atomic mass unit scale, one atom of carbon-12. It allows determination of the number of molecules or atoms by weighing them. The mole provides a bridge between the atomic world (amu) and the laboratory (grams). ![]() Since the mass of the gas can also be measured on a sensitive balance, knowing both the number of molecules and their total mass allows us to simply determine the mass of a single molecule in grams. The number in a mole is called Avogadro’s number : 6.022142 x 10 23, after the 19th-century Italian scientist who first proposed how to measure the number of molecules in a gas. Just as 1 mol of atoms contains 6.022 × 10 23 atoms, 1 mol of eggs contains 6.022 × 10 23 eggs. According to the most recent experimental measurements, this mass of carbon-12 contains 6.022142 × 10 23 atoms, but for most purposes 6.022 × 10 23 provides an adequate number of significant figures. The mole is used for this purpose.Ī mole is defined as the amount of a substance that contains the number of carbon atoms in exactly 12 g of isotopically pure carbon-12. Any readily measurable mass of an element or compound contains an extraordinarily large number of atoms, molecules, or ions, so an extraordinarily large numerical unit is needed to count them. Atoms are so small, however, that even 500 atoms are too small to see or measure by most common techniques. Sheets of printer paper are packaged in reams of 500, a seemingly large number. For example, cans of soda come in a six-pack, eggs are sold by the dozen (12), and pencils often come in a gross (12 dozen, or 144). Many familiar items are sold in numerical quantities that have unusual names. The quantity of a substance that contains the same number of units (e.g., atoms or molecules) as the number of carbon atoms in exactly 12 g of isotopically pure carbon-12., from the Latin moles, meaning “pile” or “heap” ( not from the small subterranean animal!). The unit that provides this link is the mole (mol). To analyze the transformations that occur between individual atoms or molecules in a chemical reaction it is therefore absolutely essential for chemists to know how many atoms or molecules are contained in a measurable quantity in the laboratory-a given mass of sample. In the laboratory, for example, the masses of compounds and elements used by chemists typically range from milligrams to grams, while in industry, chemicals are bought and sold in kilograms and tons. Because the masses of individual atoms are so minuscule (on the order of 10 −23 g/atom), chemists do not measure the mass of individual atoms or molecules. The problem for Dalton and other early chemists was to discover the quantitative relationship between the number of atoms in a chemical substance and its mass. We also described the law of multiple proportions, which states that the ratios of the masses of elements that form a series of compounds are small whole numbers. In Dalton’s theory each chemical compound has a particular combination of atoms and that the ratios of the numbers of atoms of the elements present are usually small whole numbers. The same calculation can also be done in a tabular format, which is especially helpful for more complex molecules:
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![]() Notably, in late 2022, user data, billing information, and vaults (with some fields encrypted and others not) were breached, leading many security professionals to call for users to change all their passwords and switch to other password managers. LastPass suffered significant security incidents between 20. On December 14, 2021, GoTo announced that LastPass would be made into a separate company and accelerate its release timeline. GoTo (formerly LogMeIn Inc.) acquired LastPass in October 2015. It also includes support for bookmarklets. The standard version of LastPass comes with a web interface, but also includes plugins for various web browsers and apps for many smartphones. But until then, avoid browser extension password managers.LastPass is a password manager distributed in subscription form as well as a freemium model with limited functionality. We need less of the "military grade encryption" marketing from them and more transparency around how often their code is audited, the results, and how they've fixed the vulnerabilities. However, the increased risk of password manager browser extensions makes these vulnerabilities severe. TeamSIK's excellent work into finding Android password manager bugs shows that the lack of security isn't necessarily limited to browser extensions, but is rather a systemic issue in the password manager ecosystem. Many of them are for-profit companies that obviously have not invested a lot of resources in an in-depth audit of their source code because of the trivial bugs that are found by researchers in an hour. The risk of having an attacker be able to directly interact with them is just too high. I don't know if these browser extension password managers will ever improve enough for me to recommend them. ![]() And if they've compromised your machine, you have bigger things to worry about. That cannot be done by efficient attackers at scale. Think of how it would be compromised: Someone would need to get at least user-level access to your computer and then either read it when it's temporarily unencrypted, or wait for you to unencrypt it. Literally anything elseĪn encrypted text file on your computer is safer than a browser extension password manager. I recommend non-technical users use the built-in password managers because they're easy to use and plenty secure. Firefox's Password Manager along with a good master password.Chrome's Password Manager along with a good sync password.Since two-factor authentication is not available for these, use a very strong and unique passphrase. All of them also offer mobile sync so you can have your passwords on the go. These are a nice choice if you dislike copying and pasting passwords into websites. Built-in browser password managersĮvery major browser now has a well-designed, built-in password manager that is easy to use. If you get all your passwords stolen by a new bug, you'll never even know, and you'll have little to no recourse. If you accidentally paste one password in the wrong place, it is easy to change. If they're reluctant, maybe you should be reluctant to put the crown jewels of your company in their hands.Ĭopying and pasting passwords into the wrong place is not a large enough risk to use a risky browser password manager extension. If you are buying a password manager from a company, you should ask to see the details of their latest source code security review. I use pass because it's simple to understand for technical folks, but I have many friends who use KeePass. Copy and paste the passwords from the app into your browser. If you do use one, do not install the browser extensions. There are many choices to choose from in this category, and none of them suffers from the direct-access-via-JavaScript risk category. What password managers should you use instead?ĭoes this mean you should give up and not use a password manager at all? No, but the choice is trickier than these companies' marketing would leave you to believe.Īny program that is not resident in your browser is safer than one that is. If you think criminals aren't mining LastPass and others for bugs right now, you're naive. If you're using it in a corporate environment to share passwords, now only one user of many needs to be attacked to steal all of your passwords via a previously undisclosed bug. Your password manager extension de jour might not be as bug ridden as LastPass, but it suffers from the same risk vector if it's a browser extension. Desktop-based password managers have no such access, as they require compromising the local machine first, which is much harder than visiting a webpage. That's how LostPass worked, and it's how many of the new attacks work, too. When you use a browser extension password manager, you give attackers an API to interact with your password manager via JavaScript or the DOM. ![]() Parallels desktop 14 mac torrent activation keygen# Therefore, It specially designed for the developers, designers, power users, and professional users to help them to be more productive every day with both of operating systems. Parallels Desktop 13 for Mac Activation Key is most trusted and tightly integrated app for running Windows apps or the Windows desktop in Apple OS X. Parallels Desktop 14.5 Crack With Activation Key You will seamlessly run both Windows and mac OS applications side by side without rebooting. Parallels Desktop 14.5 Crack With Activation Key for mac which is specially designed for the Mac OS by company Parallels. This software uses the technology of the hyper-visor. This software is more good for the user who wanted to use the Windows application on the Mac OS. 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In which he is playable using an expansive range of characters unlocking new locations, with some combat abilities which are disposable. After completing each level, the player acquires the ability to return to the free play mode. To retain the LEGO style the player has to often smash up the surroundings, rebuilding the rest of the LEGO bricks into useful things like an ice cream caravan, a switch that unlocks a locked door, a big fishing rod that helps to pick up chattels and fishes from rivers. Kick-starting generators, jumping on pressure pads, using icy cold steps by freezing waterfalls to reach cliffs every level is filled with puzzles to activate the player’s brain. The player in this game can run, smash, jump, and bash his way through exotic Ninjago movie game-themed levels by using each ninja’s distinct abilities to advance in the game. Enemies who are defeated break apart into LEGO parts and simply fade away. Several portions of the game show giant robotic dragons that shoot at enemies ships and their ground targets with expandable projectiles that accompanies colourful explosions. In this game, the battle is between characters that slam other LEGO characters with different kinds of swords, arrows, axes and spears accustomed to bright light effects which portray a style of comic book impact. While playing this game, the player can revisit the locations from the actual film, where the young ninja friends discover their true inner- self and the elemental powers, while Lloyd unearths to overcome the blot of having a demon for a dad. Transformers Rise of the Dark Spark Download PC Game For FreeĮxact plot twist as the film is seen the game narrates the story of young Lloyd and his ninja friends, who tries to defeat the foremost bad guy Garmadon, who continuous to encroach the Ninjago City.This family-friendly game is inoffensive, gruesome and contains zero sexual content which makes these game children friendly. The ESRB (Entertainment Software Rating Board) rating stays above 10 years old. It suffices as the 2nd starburst video game and the 3rd game in The Lego Movie franchise. ![]() The platforms on which this game is available are Xbox 1, PlayStation 4, Nintendo Switch and Microsoft Windows. PlayStation 4, Xbox One, Microsoft Windows, Nintendo Switch The control is not very simple, and for the newcomers it will be unusual to be behind the wheel of these cars. You will not see usual races in Drift Max Pro because the main accent is made not on the speed but on the correctness and quality of drifting.Įach car in the game is precisely traced, and during the race you will be able to see the beautiful image of your car, that will clearly make various bends. Virtually every one of them has its own twist, which distinguishes it from thousands of similar applications. Now on the expanses of the network you can find races for all tastes and capabilities of the phone. ![]() Download Drift Max Pro 2.5.15 APK – (82.8 Mb).How to Download and use the APK file to install Drift Max.Download these games right on your PC for free here at EmulatorPC. If you are overwhelmed by this multiplayer game for free, you can still try other racing games like Police Car Ramp Stunts Race 3D and Demolition Derby 3. Be the Drift King and compete players worldwide.Drive around astonishing locations in Japan, United States, and Russia during day or night.Exciting Game Features to Look Forward To Upgrading your cars is also not free as it requires cost resources. To drive the car you wish to have, you need to grind and obtain the necessary resources. Drift Max Pro offers a wide variety of cars, but not all of them are free. So, to be a drift king in the future, you need to be keen on drifting details and how to get ahead of other players.Īfter the tutorial phase, you need to purchase or upgrade your car in the garage. That way, you will know how it works as it uses realistic drifting physics. This short tutorial will be introduced during the first part of the game. If drifting is not your specialization, you can still play the game by getting into its short tutorial. Learn to Play Drift Max Pro for Beginners Once you maintain this playstyle longer, you will get a higher score. You also have to keep your drifts simultaneously. To successfully get high scores, you need to do short drifts on the straightaways and back and forth drifts. In this mode, you will unleash your drifting skills while earning rewards such as cars. If you aim to be the drift king, it is highly recommended to focus more on the “Career mode”. Each racing mode comes with different goals and rewards. What’s more, this car drifting game is also playable in different racing modes. Nevertheless, you can still enjoy your drifting journey as you will encounter stunning locations in Japan, the United States, and Russia. Getting the highest drifting score might be tough as the levels are too large to pass smoothly from one drift to the next. In Drift Max Pro, your goal is to achieve the highest score and get into new and more challenging levels. Remember that gold, card packs, cash, and more are not allowed to get cars, but you can use them to upgrade your current vehicle. These rewards will let you experience a new set of amazing cars. ![]() ![]() If you want to be a drift king someday, then this app is right for you.ĭeveloped by Tiramisu, Drift Max Pro is the newest game that lets you drift using realistic cars while earning rewards. Let’s admit it, you are one of the aspiring race car drivers that wish to drift on empty roads. Do you get excited when drifting cars in real life? Do you wish to hone your drifting skills? Then, we’ve got an excellent game for you – the Drift Max Pro. While twenty-six dimensions are far too many, they can be twisted or even folded into tiny tight compact regions in spacetime, thus possibly reducing the dimensions to four. However, problems arise when the complex mathematics of string theory indicate a need for twenty-six spatial dimensions to function. It offers a sound hypothesis of interactions on the quantum plane, from what quarks are made of to the long sought-after graviton (which mediates gravitational interaction, a massless particle with an integer spin of +/-2). String theory, while prestigious in many facets-especially in quantum mechanics and cosmology-does indeed carry flaws that can turn the universe inside out. Scientists chose "strings" over "line segments" because strings are flexible, and can be contorted in almost infinite ways, thus producing a nearly infinite spectrum of vibrational modes or "tones." Branes & Superstring Theory: If an object only has length, it must be infinitely thin (with no depth), it must therefore be envisioned as a line segment. In string theory, quarks themselves contain fragments of energy that exist on a one-dimensional plane-length. Looking at it backwards: a proton is a composite particle (or hadron) built from two up quarks and one down quark, each quark being a manifestation of the string it represents. *(While the plus sign "+" is a literal mathematical interaction, it can be seen as the interactions between the new "quarks," and effectively acts as a string/particle itself! String theorists call these gluons (g), which are responsible for the strong nuclear force and cannot exist independently (free) from such quantum systems). The result of two up quarks and one down quark produces a proton. However, when a third string that vibrates in a rather different manner (b), acts as a "down" quark, the resulting interaction simplifies as (a+a+b)* or two up quarks and one down quark. If a second string is introduced with the same properties, we now have two (a-vibrational) strings, or basically two "up" quarks. Here is a theoretical example: if a string vibrates (or wiggles) in one manner (a), it could exhibit characteristics of an "up" quark. Gubser, a physics professor at Princeton University, and author of The Little Book of String Theory, sums up the theory rather nicely, asserting that, "String theory aims to be a unifying picture, where each is a different vibrational mode of a string".Ī string's "vibrational mode" is only a fancy way of identifying the manner in which it oscillates. Image credit via MissMJ, Wikimedia Commons. In the eyes of a string theorist, all universal constituents (fermions, quarks and leptons, hadrons, bosons, and force carriers ) are defined by the vibrational mode (and usually orientation) of its string.ĭifferent levels of magnification of matter (1-5), ending with the string level (6). General quantum strings are approximated to be 10 -33Ĭm in length (that's pretty amazingly small). ![]() According to string theory, "strings" are tiny bits of pure energy that are the smallest constituents of matter and force interaction in our universe. String theory states that all matter in the universe is composed of tiny 1-dimensional strings, not point particles (which are 0-dimensional in nature). That's where "superstring theory" comes in. However, how can it possibly work? After all, we only experience four dimensions (three of space and one of time), so 26 dimensions is 22 too many. ![]() A theory with 26 dimensions, objects with imaginary mass that could ruin the very physics of our universe, and the notion that particles and forces are only excitations of vibrational modes-string theory, and all that it entails, is mind-boggling. ![]() The Dominators attack systems on their own, and those systems defend themselves however possible. Your mission is to help save the galaxy while amassing your own personal fortune. Space Rangers HD is the re-release of Space Rangers 2: Dominators, a cult classic from 2004. The game thrusts you into the role of an independent pilot navigating a galaxy under siege by vicious AI warriors bent on domination. ![]() You may also want to check out X3: Albion Prelude, a sorta-sequel that builds on Terran Conflict and provides a new campaign. There’s a new game, X3: Rebirth, but it’s harshly criticized for bugs, lack of content and poor optimization. And, since its offline, you can install mods! Once you’re comfortable with it, though, X3 is the closest you can get to Eve Online without actually playing it. You’ll need to read some fan-made tutorials online and keep the X3 wiki at the ready. Nothing’s explained well and you can quickly find yourself dead or, worse, bored. Unfortunately, X3: Terran Conflict has another similarity to Eve a hopelessly obtuse interface and general disinterest in helping new players get into the game. The game world isn’t as large as Eve Online, but the options are similar. You can fight it out as a combat pilot, learn intergalactic trade, or explore the stars. Like Eve, X3: Terran Conflict takes place in a large universe with many possibilities. This is undoubtedly the most Eve-like of the games listed here. ![]() You can download the game from the developer’s website or Steam. I’ve already penned a full review of the game, so check it out if you’re interested. While the game doesn't include capital ships, it does have vessels ranging in size from tiny, agile interceptors to lumbering, heavily armed frigates. Your shots travel where you point them and, in the case of projectile weapons, you need to lead your target. Unlike Eve, where a hit is often determined by stats, Star Conflict operates as a third-person shooter. 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In Figure 1, the demolition crew has already started removing the bridge before the reconnaissance team could inspect the damage (the team started in Sacramento and were escorted by the California Highway Patrol down I-5 through various detours to a hotel in Pasadena). During the earthquake, the outer frames rotated, failing the restrainers, followed by unseating and collapse of the cantilevered spans. A retrofit in 1974 added restrainers at the hinges. These two parallel 741-foot-long bridges (53 1797L/R) built in 1955, were designed with table-like center frames that supported the cantilevered spans of the four end frames on highly skewed, 8-inch-long hinge seats. Seven bridges, five of which were designed before 1971, were severely damaged during the earthquake but all 60 bridges in the Los Angeles area that had been retrofitted after the Loma Prieta Earthquake performed very well. The need to quickly complete the retrofit program was demonstrated again when the 1994 Northridge Earthquake occurred before the program was completed. Thus, the Caltrans Seismic Advisory Board was formed and continues to advise Caltrans on seismic issues. The Board of Inquiry recommended that a standing board of experts should be created to advise Caltrans on its earthquake engineering practices. During the earthquake, the soil shook violently, dragging the piles from their connection with the superstructure which resulted in the pile extensions punching through the bridge deck.Ĭoncerns about the bridge damage prompted the California governor to create a Board of Inquiry that found that Caltrans was doing a good job addressing seismic issues but needed to accelerate the seismic retrofit program. The Struve Slough Bridges (36 0088L/R) in Watsonville were T-girder bridges on piles founded on very soft soil. Also, a 50-foot span over Pier 9 on the East Crossing of the San Francisco Oakland Bay Bridge (33 0025),īuilt in the 1930s, collapsed due to inadequate 4-inch-wide seats, reiterating the lesson that seats have to be long enough to support the resulting displaced bridge members during earthquakes. Several other double-deck viaducts around San Francisco sustained severe damage to the superstructure-to-column connections that resulted in their closure and removal after the earthquake. This resulted in the collapse of a mile-long segment of the viaduct during the earthquake. The main reinforcement in these connections was not sufficiently developed, and the shear reinforcement was inadequate. The earthquake damaged the double-deck Cypress Viaduct (33 0178), built in the 1950s, that had been designed with vulnerable pinned connections to make it structurally determinant and easier to analyze. Unfortunately, the 1989 Loma Prieta Earthquake occurred before many bridges were retrofitted. The previous retrofit program relied on cable restrainers to limit displacement and prevent column damage, but shear damage to the short columns on the Route 605/5 Separation (53 1660) generated enough concern to begin a new retrofit program to wrap bridge columns in steel (or fiber-reinforced polymer) casings on older bridges. The 1987 Whittier Narrows Earthquake was another turning point in Caltrans seismic design of bridges. ![]() The San Fernando Earthquake was also the start of the practice of Caltrans sending out a reconnaissance team of licensed engineers to study the damage and write a report with lessons learned, a practice that has continued for every subsequent large earthquake. Caltrans also started a seismic retrofit program to address the many existing bridges that had been under-designed for earthquakes. ![]() Other changes included the development of a site-specific ground shaking hazard for designing bridges and a capacity-based design method that relied on structural column fuses to limit seismic forces. Also, the minimum seat length at expansion joints, abutment seats, and hinges went from 12 inches to 18 inches (and later to 24 inches). Immediately afterward, Caltrans wrote construction change orders requiring more transverse reinforcement and continuous main reinforcement in bridge columns and eliminating a vulnerable lap splice connecting the footing to the column. Bridges at that time were designed for a small seismic force, which resulted in extensive damage to bridges and interchanges during the earthquake. The most significant changes occurred after the 1971 San Fernando Earthquake. Every damaging California earthquake has resulted in changes to the California Department of Transportation’s (Caltrans’) seismic practice. |