The iPod is a line of portable media players and multi-purpose pocket computers designed and marketed by Apple Inc. The first version was released on October 23, 2001, about 8 1⁄2 months after the Macintosh version of iTunes was released; as of July 27, 2017, only the iPod Touch remains in production. Like other digital music players, iPods can serve as external data storage devices. Apple's iTunes software can be used to transfer music, videos, contact information, e-mail settings, Web bookmarks, calendars, to the devices supporting these features from computers using certain versions of Apple macOS and Microsoft Windows operating systems. Before the release of iOS 5, the iPod branding was used for the media player included with the iPhone and iPad, a combination of the Music and Videos apps on the iPod Touch; as of iOS 5, separate apps named "Music" and "Videos" are standardized across all iOS-powered products. While the iPhone and iPad have the same media player capabilities as the iPod line, they are treated as separate products.
During the middle of 2010, iPhone sales overtook those of the iPod. The iPod was released in late 2001; the iPod line came from Apple's "digital hub" category, when the company began creating software for the growing market of personal digital devices. Digital cameras and organizers had well-established mainstream markets, but the company found existing digital music players "big and clunky or small and useless" with user interfaces that were "unbelievably awful," so Apple decided to develop its own; as ordered by CEO Steve Jobs, Apple's hardware engineering chief Jon Rubinstein assembled a team of engineers to design the iPod line, including hardware engineers Tony Fadell and Michael Dhuey, design engineer Sir Jonathan Ive. Rubinstein had discovered the Toshiba hard disk drive while meeting with an Apple supplier in Japan, purchased the rights to it for Apple, had already worked out how the screen and other key elements would work; the aesthetic was inspired by the 1958 Braun T3 transistor radio designed by Dieter Rams, while the wheel-based user interface was prompted by Bang & Olufsen's BeoCom 6000 telephone.
The product was developed in less than one year and unveiled on October 23, 2001. Jobs announced it as a Mac-compatible product with a 5 GB hard drive that put "1,000 songs in your pocket."Apple did not develop the iPod software in-house, instead using PortalPlayer's reference platform based on two ARM cores. The platform had rudimentary software running on a commercial microkernel embedded operating system. PortalPlayer had been working on an IBM-branded MP3 player with Bluetooth headphones. Apple contracted another company, Pixo, to help design and implement the user interface under the direct supervision of Steve Jobs; as development progressed, Apple continued to feel. Starting with the iPod Mini, the Chicago font was replaced with Espy Sans. IPods switched fonts again to Podium Sans—a font similar to Apple's corporate font, Myriad. Color display iPods adopted some Mac OS X themes like Aqua progress bars, brushed metal meant to evoke a combination lock. In 2007, Apple modified the iPod interface again with the introduction of the sixth-generation iPod Classic and third-generation iPod Nano by changing the font to Helvetica and, in most cases, splitting the screen in half by displaying the menus on the left and album artwork, photos, or videos on the right.
In 2006 Apple presented a special edition for iPod 5G of Irish rock band U2. Like its predecessor, this iPod has engraved the signatures of the four members of the band on its back, but this one was the first time the company changed the colour of the metal; this iPod was only available with 30GB of storage capacity. The special edition entitled purchasers to an exclusive video with 33 minutes of interviews and performance by U2, downloadable from the iTunes Store. In September 2007, during a lawsuit with patent holding company Burst.com, Apple drew attention to a patent for a similar device, developed in 1979. Kane Kramer applied for a UK patent for his design of a "plastic music box" in 1981, which he called the IXI, he was unable to secure funding to renew the US$120,000 worldwide patent, so it lapsed and Kramer never profited from his idea. The name iPod was proposed by Vinnie Chieco, a freelance copywriter, called by Apple to figure out how to introduce the new player to the public. After Chieco saw a prototype, he thought of the movie 2001: A Space Odyssey and the phrase "Open the pod bay doors, Hal", which refers to the white EVA Pods of the Discovery One spaceship.
Chieco saw an analogy to the relationship between the spaceship and the smaller independent pods in the relationship between a personal computer and the music player. Apple researched the trademark and found that it was in use. Joseph N. Grasso of New Jersey had listed an "iPod" trademark with the U. S. Patent and Trademark Office in July 2000 for Internet kiosks; the first iPod kiosks had been demonstrated to the public in New Jersey in March 1998, commercial use began in January 2000, but had been discontinued by 2001. The trademark was registered by the USPTO in November 2003, Grasso assigned it to Apple Computer, Inc. in 2005. The earliest recorded use in commerce of an "iPod" trademark was in 1991 by Chrysalis Corp. of Sturgis, styled "iPOD". In mid-2015, several new color schemes for all of the current iPod models were spotted in the latest version of iTunes, 12.2. Belgian website Belgium iPhone found the images
University of Toronto
The University of Toronto is a public research university in Toronto, Canada, located on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution of higher learning in the colony of Upper Canada. Controlled by the Church of England, the university assumed the present name in 1850 upon becoming a secular institution; as a collegiate university, it comprises eleven colleges, which differ in character and history, each with substantial autonomy on financial and institutional affairs. It has two satellite campuses in Mississauga; the university is ranked as the best Canadian university, according to various major publications. Academically, the University of Toronto is noted for influential movements and curricula in literary criticism and communication theory, known collectively as the Toronto School; the university was the birthplace of insulin and stem cell research, was the site of the first practical electron microscope, the development of deep learning, multi-touch technology, the identification of the first black hole Cygnus X-1, the development of the theory of NP-completeness.
By a significant margin, it receives the most annual scientific research funding of any Canadian university. It is one of two members of the Association of American Universities outside the United States, the other being McGill University in Montreal, Canada; the Varsity Blues are the athletic teams that represent the university in intercollegiate league matches, with long and storied ties to gridiron football and ice hockey. The earliest recorded college football game was played in the University of Toronto's University College in the 1860s; the university's Hart House is an early example of the North American student centre serving cultural and recreational interests within its large Gothic-revival complex. The University of Toronto has educated three Governors General of Canada, four Prime Ministers of Canada, four foreign leaders, fourteen Justices of the Supreme Court; as of March 2019, ten Nobel laureates, five Turing Award winners, 94 Rhodes Scholars, one Fields Medalist have been affiliated with the university.
The founding of a colonial college had long been the desire of John Graves Simcoe, the first Lieutenant-Governor of Upper Canada. As an Oxford-educated military commander who had fought in the American Revolutionary War, Simcoe believed a college was needed to counter the spread of republicanism from the United States; the Upper Canada Executive Committee recommended in 1798 that a college be established in York, the colonial capital. On March 15, 1827, a royal charter was formally issued by King George IV, proclaiming "from this time one College, with the style and privileges of a University... for the education of youth in the principles of the Christian Religion, for their instruction in the various branches of Science and Literature... to continue for to be called King's College." The granting of the charter was the result of intense lobbying by John Strachan, the influential Anglican Bishop of Toronto who took office as the college's first president. The original three-storey Greek Revival school building was built on the present site of Queen's Park.
Under Strachan's stewardship, King's College was a religious institution aligned with the Church of England and the British colonial elite, known as the Family Compact. Reformist politicians opposed the clergy's control over colonial institutions and fought to have the college secularized. In 1849, after a lengthy and heated debate, the newly elected responsible government of Upper Canada voted to rename King's College as the University of Toronto and severed the school's ties with the church. Having anticipated this decision, the enraged Strachan had resigned a year earlier to open Trinity College as a private Anglican seminary. University College was created as the nondenominational teaching branch of the University of Toronto. During the American Civil War, the threat of Union blockade on British North America prompted the creation of the University Rifle Corps, which saw battle in resisting the Fenian raids on the Niagara border in 1866; the Corps was part of the Reserve Militia lead by Professor Henry Croft.
Established in 1878, the School of Practical Science was precursor to the Faculty of Applied Science and Engineering, nicknamed Skule since its earliest days. While the Faculty of Medicine opened in 1843, medical teaching was conducted by proprietary schools from 1853 until 1887, when the faculty absorbed the Toronto School of Medicine. Meanwhile, the university continued to confer medical degrees; the university opened the Faculty of Law in 1887, followed by the Faculty of Dentistry in 1888, when the Royal College of Dental Surgeons became an affiliate. Women were first admitted to the university in 1884. A devastating fire in 1890 gutted the interior of University College and destroyed 33,000 volumes from the library, but the university restored the building and replenished its library within two years. Over the next two decades, a collegiate system took shape as the university arranged federation with several ecclesiastical colleges, including Strachan's Trinity College in 1904; the university operated the Royal Conservatory of Music from 1896 to 1991 and the Royal Ontario Museum from 1912 to 1968.
The University of Toronto Press was founded in 1901 as Canada's first academic publishing house. The Faculty of Forestry, founded in 1907 with Bernhard Fernow as dean, was Canada's first university faculty devoted to forest science. In 1910, the Faculty of Education opened its laboratory school, the University of Toro
California is a state in the Pacific Region of the United States. With 39.6 million residents, California is the most populous U. S. the third-largest by area. The state capital is Sacramento; the Greater Los Angeles Area and the San Francisco Bay Area are the nation's second and fifth most populous urban regions, with 18.7 million and 9.7 million residents respectively. Los Angeles is California's most populous city, the country's second most populous, after New York City. California has the nation's most populous county, Los Angeles County, its largest county by area, San Bernardino County; the City and County of San Francisco is both the country's second-most densely populated major city after New York City and the fifth-most densely populated county, behind only four of the five New York City boroughs. California's $3.0 trillion economy is larger than that of any other state, larger than those of Texas and Florida combined, the largest sub-national economy in the world. If it were a country, California would be the 5th largest economy in the world, the 36th most populous as of 2017.
The Greater Los Angeles Area and the San Francisco Bay Area are the nation's second- and third-largest urban economies, after the New York metropolitan area. The San Francisco Bay Area PSA had the nation's highest GDP per capita in 2017 among large PSAs, is home to three of the world's ten largest companies by market capitalization and four of the world's ten richest people. California is considered a global trendsetter in popular culture, innovation and politics, it is considered the origin of the American film industry, the hippie counterculture, fast food, the Internet, the personal computer, among others. The San Francisco Bay Area and the Greater Los Angeles Area are seen as global centers of the technology and entertainment industries, respectively. California has a diverse economy: 58% of the state's economy is centered on finance, real estate services and professional, scientific and technical business services. Although it accounts for only 1.5% of the state's economy, California's agriculture industry has the highest output of any U.
S. state. California is bordered by Oregon to the north and Arizona to the east, the Mexican state of Baja California to the south; the state's diverse geography ranges from the Pacific Coast in the west to the Sierra Nevada mountain range in the east, from the redwood–Douglas fir forests in the northwest to the Mojave Desert in the southeast. The Central Valley, a major agricultural area, dominates the state's center. Although California is well-known for its warm Mediterranean climate, the large size of the state results in climates that vary from moist temperate rainforest in the north to arid desert in the interior, as well as snowy alpine in the mountains. Over time and wildfires have become more pervasive features. What is now California was first settled by various Native Californian tribes before being explored by a number of European expeditions during the 16th and 17th centuries; the Spanish Empire claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its successful war for independence but was ceded to the United States in 1848 after the Mexican–American War.
The western portion of Alta California was organized and admitted as the 31st state on September 9, 1850. The California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom; the word California referred to the Baja California Peninsula of Mexico. The name derived from the mythical island California in the fictional story of Queen Calafia, as recorded in a 1510 work The Adventures of Esplandián by Garci Rodríguez de Montalvo; this work was the fifth in a popular Spanish chivalric romance series that began with Amadis de Gaula. Queen Calafia's kingdom was said to be a remote land rich in gold and pearls, inhabited by beautiful black women who wore gold armor and lived like Amazons, as well as griffins and other strange beasts. In the fictional paradise, the ruler Queen Calafia fought alongside Muslims and her name may have been chosen to echo the title of a Muslim leader, the Caliph. It's possible.
Know ye that at the right hand of the Indies there is an island called California close to that part of the Terrestrial Paradise, inhabited by black women without a single man among them, they lived in the manner of Amazons. They were robust of body with great virtue; the island itself is one of the wildest in the world on account of the craggy rocks. Shortened forms of the state's name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. Various estimates of the native population range from 100,000 to 300,000; the Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups were diverse in their political organization with bands, villages, on the resource-rich coasts, large chiefdoms, such as the Chumash and Salinan.
Trade, intermarriage a
The iPad Pro family is a line of iPad tablet computers designed and marketed by Apple Inc. that runs the iOS mobile operating system. Its current generation is available in two screen sizes, 11-inch and 12.9-inch, each with four options for internal storage capacities: 64, 256, 512 GB, or 1 TB. The first iPad Pro, the 12.9-inch version, was announced on September 9, 2015, released on November 11, 2015. It is larger than all previous iPad models and the first iPad tablet to feature LPDDR4 RAM; the 12.9-inch tablet was followed by the smaller 9.7-inch version, announced on March 21, 2016, released on March 31 that same year. On June 5, 2017, the second generation iPad Pro was announced, which features A10X Fusion processors, with basic storage of 64 GB, optional 512 GB. Upgraded displays include a new 10.5-inch version to replace the 9.7-inch model, while the 12.9-inch version was refreshed. Following this announcement, both models of the first generation iPad; the third generation of iPad Pro was announced on October 30, 2018.
It is available in two screen sizes: 12.9-inch. They feature full screen displays, with the 11-inch model replacing the 10.5-inch model of the previous generation. They feature up to 1 TB of storage and Face ID which works in both vertical and horizontal orientations, a feature that does not apply to iPhones with Face ID; the third generation does not feature a home button. The 12.9-inch version of the iPad Pro was announced during an Apple Special Event on September 9, 2015. It was released on November 11, 2015 with gold and space gray color options. Prices ranging from US$799.99 to $1,229.99 based on cellular connectivity. On March 21, 2016, the 9.7 inch version of the iPad Pro was announced at an Apple keynote with an additional rose gold color option. The 9.7 inch version introduced the ability to choose base 32GB Model with Cellular + WiFi option. The 9.7 inch model is priced from $599 to $1,129 depending on the configuration. It was released on March 31, 2016; the 9.7-inch iPad Pro, when compared to the iPad Air 2, features a faster CPU, a better camera, is the first iPad to feature True Tone Flash and Retina Flash.
It had the highest storage for an iPad at the time with a 256 GB storage option and has a True Tone display, which allows the LCD to adapt to ambient lighting to change its color and intensity in different environments. Both iPad Pro models include the Apple M9 motion co-processor; the 9.7 inch model, has a underclocked CPU and only 2 GB of RAM. A number of features are carried over from the standard iPad, such as Touch ID and the Retina Display. New features include a smart connector for a keyboard and four stereo speakers located in pairs on top and bottom of the device; the 12.9 inch model has a 2732-by-2048 Retina Display at 264 pixels per inch, the 9.7 inch model has a 2048-by-1536 Retina Display at 264 pixels per inch and features a variable refresh rate, a first for Apple. The 12.9 inch version of the iPad Pro is the first iPad to include 4 GB of RAM. A customized 12.9 inch iPad Pro was designed by Jony Ive and submitted to the Time for Design auction. The special edition iPad Pro has an "Edition 1 of 1" label engraved on its back and comes with a custom yellow-gold anodised finish, a blue leather Smart Cover and an orange leather Apple Pencil case cover, all of which are not sold by Apple elsewhere.
The second generation of iPad Pro was announced on June 5, 2017 alongside iOS 11 at the 2017 WWDC. The second-generation iPad Pro models, at 10.5-inch and 12.9-inch, have an A10X hexa-core CPU and with a 12-core GPU, Apple's ProMotion display technology which supports HDR10 and Dolby Vision content with a 120 Hz refresh rate and their True Tone display is 50 percent brighter than the earlier models. They have USB-C connection speeds using Lightning cables, with USB-C fast-charge support; the second generation iPad Pro has storage capacities up to 512 GB. On March 18, 2019, the 10.5-inch iPad Pro was replaced by a 10.5-inch iPad Air. The third generation of iPad Pro was announced on October 30, 2018, during an Apple Special Event at the Howard Gilman Opera House in Brooklyn, New York; the redesigned 2018 models feature new edge-to-edge Liquid Retina displays, Face ID, improved 12MP and 7MP cameras, USB-C connectors, Apple A12X Bionic processors. The tablets are offered in 11-inch and 12.9-inch sizes, are the first iPad models to offer tap-to-wake LCD displays, up to 1TB of internal storage.
Additionally, the third generation tablets lack both a headphone jack. They are only available in silver and space gray. There are four accessories made for iPad Pro, all of which are sold separately: a "smart" screen cover. Smart Keyboard docks with iPad Pro using the Smart Connector, a magnetic connection that provides data transfer and power. Smart Keyboard, which doubles as a kickstand, is comparable to that of the competing Microsoft Surface Pro; the design of the Smart Keyboard is similar to the design of the Smart Cover accessory. The first generation Apple Pencil is a precision stylus exclusive to the iPad Pro, iPad 2018, the iPad Air a
IPhone is a line of smartphones designed and marketed by Apple Inc. All generations of the iPhone use Apple's iOS mobile operating system software; the first-generation iPhone was released on June 29, 2007, multiple new hardware iterations with new iOS releases have been released since. The user interface is built around the device's multi-touch screen, including a virtual keyboard; the iPhone can connect to cellular networks. An iPhone can shoot video, take photos, play music and receive email, browse the web and receive text messages, follow GPS navigation, record notes, perform mathematical calculations, receive visual voicemail. Other functionality, such as video games, reference works, social networking, can be enabled by downloading mobile apps; as of January 2017, Apple's App Store contained more than 2.2 million applications available for the iPhone. Apple has released twelve generations of iPhone models, each accompanied by one of the twelve major releases of the iOS operating system.
The original first-generation iPhone was a GSM phone and established design precedents, such as a button placement that has persisted throughout all releases and a screen size maintained for the next four iterations. The iPhone 3G added 3G network support, was followed by the 3GS with improved hardware, the 4 with a metal chassis, higher display resolution and front-facing camera, the 4S with improved hardware and the voice assistant Siri; the iPhone 5 featured Apple's newly introduced Lightning connector. In 2013, Apple released the 5S with improved hardware and a fingerprint reader, the lower-cost 5C, a version of the 5 with colored plastic casings instead of metal, they were followed by the larger iPhone 6, with models featuring 4.7-and-5.5-inch displays. The iPhone 6S was introduced the following year, which featured hardware upgrades and support for pressure-sensitive touch inputs, as well as the SE—which featured hardware from the 6S but the smaller form factor of the 5S. In 2016, Apple unveiled the iPhone 7 and 7 Plus, which add water resistance, improved system and graphics performance, a new rear dual-camera setup on the Plus model, new color options, while removing the 3.5 mm headphone jack found on previous models.
The iPhone 8 and 8 Plus were released in 2017, adding a glass back and an improved screen and camera. The iPhone X was released alongside the 8 and 8 Plus, with its highlights being a near bezel-less design, an improved camera and a new facial recognition system, named Face ID, but having no home button, therefore, no Touch ID. In September 2018, Apple again released 3 new iPhones, which are the iPhone XS, an upgraded version of the since discontinued iPhone X, iPhone XS Max, a larger variant with the series' biggest display as of 2018 and iPhone XR, a lower end version of the iPhone X; the original iPhone was described as "revolutionary" and a "game-changer" for the mobile phone industry. Subsequent iterations of the iPhone have garnered praise; the iPhone is one of the most used smartphones in the world, its success has been credited with helping Apple become one of the world's most valuable publicly traded companies. Development of what was to become the iPhone began in 2004, when Apple started to gather a team of 1,000 employees to work on the confidential "Project Purple."
Apple CEO Steve Jobs steered the original focus away from a tablet towards a phone. Apple created the device during a secretive collaboration with Cingular Wireless at the time—at an estimated development cost of US$150 million over thirty months. According to Steve Jobs, the "i" word in "iMac" stands for internet, instruct and inspire. Apple rejected the "design by committee" approach that had yielded the Motorola ROKR E1, a unsuccessful collaboration with Motorola. Among other deficiencies, the ROKR E1's firmware limited storage to only 100 iTunes songs to avoid competing with Apple's iPod nano. Cingular gave Apple the liberty to develop the iPhone's hardware and software in-house and paid Apple a fraction of its monthly service revenue, in exchange for four years of exclusive US sales, until 2011. Jobs unveiled the iPhone to the public on January 9, 2007, at the Macworld 2007 convention at the Moscone Center in San Francisco; the two initial models, a 4 GB model priced at US$499 and an 8 GB model at US$599, went on sale in the United States on June 29, 2007, at 6:00 pm local time, while hundreds of customers lined up outside the stores nationwide.
The passionate reaction to the launch of the iPhone resulted in sections of the media dubbing it the'Jesus phone'. Following this successful release in the US, the first generation iPhone was made available in the UK, Germany in November 2007, Ireland and Austria in the spring of 2008. On July 11, 2008, Apple released the iPhone 3G including the original six. Apple released the iPhone 3G in upwards of eighty territories. Apple announced the iPhone 3GS on June 8, 2009, along with plans to release it in June and August, starting with the US, Canada and major European countries on June 19. Many would-be users objected to the iPhone's cost, 40% of users had household incomes over US$100,000; the back of the original first generation iPhone was made of aluminum with a black plastic accent. The iPhone 3G and 3GS feature a full plastic back to increase the strength of the GSM signal; the iPhone 3G was available in
Quantum dots are tiny semiconductor particles a few nanometres in size, having optical and electronic properties that differ from larger LED particles. They are a central theme in nanotechnology; when the quantum dots are illuminated by UV light, some of the electrons receive enough energy to break free from the atoms. This capability allows them to move around the nanoparticle, creating a conductance band in which electrons are free to move through a material and conduct electricity; when these electrons drop back into the outer orbit around the atom, as illustrated in the following figure, they emit light. The color of that light depends on the energy difference between the conductance band and the valence band. In the language of materials science, nanoscale semiconductor materials confine either electrons or electron holes. Quantum dots are sometimes referred to as artificial atoms, emphasizing their singularity, having bound, discrete electronic states, like occurring atoms or molecules.
Quantum dots have properties intermediate between bulk semiconductors and discrete atoms or molecules. Their optoelectronic properties change as a function of both shape. Larger QDs of 5–6 nm diameter emit longer wavelengths, with colors such as orange or red. Smaller QDs emit shorter wavelengths, yielding colors like blue and green, although the specific colors and sizes vary depending on the exact composition of the QD; because of their tunable properties, QDs are of wide interest. Potential applications include transistors, solar cells, LEDs, diode lasers and second-harmonic generation, quantum computing, medical imaging, their small size allows for QDs to be suspended in solution, which may lead to use in inkjet printing and spin-coating. They have been used in Langmuir-Blodgett thin-films; these processing techniques result in less expensive and less time-consuming methods of semiconductor fabrication. There are several ways to prepare the principal ones involving colloids. Colloidal semiconductor nanocrystals are synthesized from solutions, much like traditional chemical processes.
The main difference remains dissolved. Heating the solution at high temperature, the precursors decompose forming monomers which nucleate and generate nanocrystals. Temperature is a critical factor in determining optimal conditions for the nanocrystal growth, it must be high enough to allow for rearrangement and annealing of atoms during the synthesis process while being low enough to promote crystal growth. The concentration of monomers is another critical factor that has to be stringently controlled during nanocrystal growth; the growth process of nanocrystals can occur in two different regimes, "focusing" and "defocusing". At high monomer concentrations, the critical size is small, resulting in growth of nearly all particles. In this regime, smaller particles grow faster than large ones resulting in "focusing" of the size distribution to yield nearly monodisperse particles; the size focusing is optimal when the monomer concentration is kept such that the average nanocrystal size present is always larger than the critical size.
Over time, the monomer concentration diminishes, the critical size becomes larger than the average size present, the distribution "defocuses". There are colloidal methods to produce many different semiconductors. Typical dots are made of binary compounds such as lead sulfide, lead selenide, cadmium selenide, cadmium sulfide, cadmium telluride, indium arsenide, indium phosphide. Dots may be made from ternary compounds such as cadmium selenide sulfide; these quantum dots can contain as few as 100 to 100,000 atoms within the quantum dot volume, with a diameter of ≈10 to 50 atoms. This corresponds to about 2 to 10 nanometers, at 10 nm in diameter, nearly 3 million quantum dots could be lined up end to end and fit within the width of a human thumb. Large batches of quantum dots may be synthesized via colloidal synthesis. Due to this scalability and the convenience of benchtop conditions, colloidal synthetic methods are promising for commercial applications, it is acknowledged to be the least toxic of all the different forms of synthesis.
Plasma synthesis has evolved to be one of the most popular gas-phase approaches for the production of quantum dots those with covalent bonds. For example and germanium quantum dots have been synthesized by using nonthermal plasma; the size, shape and composition of quantum dots can all be controlled in nonthermal plasma. Doping that seems quite challenging for quantum dots has been realized in plasma synthesis. Quantum dots synthesized by plasma are in the form of powder, for which surface modification may be carried out; this can lead to excellent dispersion of quantum dots in either organic solvents or water. Self-assembled quantum dots are between 5 and 50 nm in size. Quantum dots defined by lithographically patterned gate electrodes, or by etching on two-dimensional electron gasses in semiconductor heterostructures can have lateral dimensions between 20 and 100 nm; some quantum dots are small regions of one material buried in another with a larger band gap. These can be so-called core–shell structures, e.g. with CdSe in the core and ZnS in the shell, or from special forms of silica called ormosil.
Sub-monolayer shells can be effective ways of passivating the quantum dots, such as PbS cores with sub-monolayer CdS shells. Quantum dots sometimes occur spontaneously in quantum well structures due to monolayer fluctuations in the well's thickness. Self-asse
Apple Inc. is an American multinational technology company headquartered in Cupertino, that designs and sells consumer electronics, computer software, online services. It is considered one of the Big Four of technology along with Amazon and Facebook; the company's hardware products include the iPhone smartphone, the iPad tablet computer, the Mac personal computer, the iPod portable media player, the Apple Watch smartwatch, the Apple TV digital media player, the HomePod smart speaker. Apple's software includes the macOS and iOS operating systems, the iTunes media player, the Safari web browser, the iLife and iWork creativity and productivity suites, as well as professional applications like Final Cut Pro, Logic Pro, Xcode, its online services include the iTunes Store, the iOS App Store, Mac App Store, Apple Music, Apple TV+, iMessage, iCloud. Other services include Apple Store, Genius Bar, AppleCare, Apple Pay, Apple Pay Cash, Apple Card. Apple was founded by Steve Jobs, Steve Wozniak, Ronald Wayne in April 1976 to develop and sell Wozniak's Apple I personal computer, though Wayne sold his share back within 12 days.
It was incorporated as Apple Computer, Inc. in January 1977, sales of its computers, including the Apple II, grew quickly. Within a few years and Wozniak had hired a staff of computer designers and had a production line. Apple went public in 1980 to instant financial success. Over the next few years, Apple shipped new computers featuring innovative graphical user interfaces, such as the original Macintosh in 1984, Apple's marketing advertisements for its products received widespread critical acclaim. However, the high price of its products and limited application library caused problems, as did power struggles between executives. In 1985, Wozniak departed Apple amicably and remained an honorary employee, while Jobs and others resigned to found NeXT; as the market for personal computers expanded and evolved through the 1990s, Apple lost market share to the lower-priced duopoly of Microsoft Windows on Intel PC clones. The board recruited CEO Gil Amelio to what would be a 500-day charge for him to rehabilitate the financially troubled company—reshaping it with layoffs, executive restructuring, product focus.
In 1997, he led Apple to buy NeXT, solving the failed operating system strategy and bringing Jobs back. Jobs pensively regained leadership status, becoming CEO in 2000. Apple swiftly returned to profitability under the revitalizing Think different campaign, as he rebuilt Apple's status by launching the iMac in 1998, opening the retail chain of Apple Stores in 2001, acquiring numerous companies to broaden the software portfolio. In January 2007, Jobs renamed the company Apple Inc. reflecting its shifted focus toward consumer electronics, launched the iPhone to great critical acclaim and financial success. In August 2011, Jobs resigned as CEO due to health complications, Tim Cook became the new CEO. Two months Jobs died, marking the end of an era for the company. Apple is well known for its size and revenues, its worldwide annual revenue totaled $265 billion for the 2018 fiscal year. Apple is the world's largest information technology company by revenue and the world's third-largest mobile phone manufacturer after Samsung and Huawei.
In August 2018, Apple became the first public U. S. company to be valued at over $1 trillion. The company employs 123,000 full-time employees and maintains 504 retail stores in 24 countries as of 2018, it operates the iTunes Store, the world's largest music retailer. As of January 2018, more than 1.3 billion Apple products are in use worldwide. The company has a high level of brand loyalty and is ranked as the world's most valuable brand. However, Apple receives significant criticism regarding the labor practices of its contractors, its environmental practices and unethical business practices, including anti-competitive behavior, as well as the origins of source materials. Apple Computer Company was founded on April 1, 1976, by Steve Jobs, Steve Wozniak, Ronald Wayne; the company's first product is the Apple I, a computer designed and hand-built by Wozniak, first shown to the public at the Homebrew Computer Club. Apple I was sold as a motherboard —a base kit concept which would now not be marketed as a complete personal computer.
The Apple I went on sale in July 1976 and was market-priced at $666.66. Apple Computer, Inc. was incorporated on January 3, 1977, without Wayne, who had left and sold his share of the company back to Jobs and Wozniak for $800 only twelve days after having co-founded Apple. Multimillionaire Mike Markkula provided essential business expertise and funding of $250,000 during the incorporation of Apple. During the first five years of operations revenues grew exponentially, doubling about every four months. Between September 1977 and September 1980, yearly sales grew from $775,000 to $118 million, an average annual growth rate of 533%; the Apple II invented by Wozniak, was introduced on April 16, 1977, at the first West Coast Computer Faire. It differs from its major rivals, the TRS-80 and Commodore PET, because of its character cell-based color graphics and open architecture. While early Apple II models use ordinary cassette tapes as storage devices, they were superseded by the introduction of a 5 1⁄4-inch floppy disk drive and interface called the Disk II.
The Apple II was chosen to be the desktop platform for the first "killer app" of the business world: VisiCalc, a spreadsheet program. VisiCalc created a business market for the Apple II and gave home users an additional reason to buy an Apple II: compatibility with the office. Before VisiCalc, Apple had been a distant third place c