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Lucrare de atestat la Limba Engleza - Thomas Alva Edison

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Colegiul National Pedagogic 'Constantin Bratescu'

Lucrare de atestat la Limba Engleza

Thomas Alva Edison




Thomas Alva Edison

Introduction

Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman who developed many devices which greatly influenced life around the world. Dubbed 'The Wizard of Menlo Park' by a newspaper reporter, he was one of the first inventors to apply the principles of mass production to the process of invention, and therefore is often credited with the creation of the first industrial research laboratory.

Some of his inventions were not completely original but amounted to improvements of earlier inventions. Also, many of the inventions attributed to him were actually created by one or more of the numerous employees working under his direction. Nevertheless, Edison is considered one of the most prolific inventors in history, holding 1,097 U.S. patents in his name, as well as many patents in the United Kingdom, France and Germany.

Structured in three chapters, the paper starts by describing Thomas Edison’s life bla bla . The second chapter presents all his important inventions and the third chapter makes a walk through his failed inventions.

The reason why I have chosen this subject is because Thomas Edison was more responsible than any one else for creating the modern world . No one did more too shape the physical/cultural makeup of present day civilization. Accordingly, he was the most influential figure of the millennium.'

Edison at 14

The Life of Thomas Edison

Thomas Alva Edison was born on February 11, 1847 in Milan, Ohio; the seventh and last child of Samuel and Nancy Edison. When Edison was seven his family moved to Port Huron, Michigan. Edison lived here until he struck out on his own at the age of sixteen. Edison had very little formal education as a child, attending school only for a few months. He was taught reading, writing, and arithmetic by his mother, but was always a very curious child and taught himself much by reading on his own. This belief in self-improvement remained throughout his life.

Edison began working at an early age, as most boys did at the time. At thirteen he took a job as a newsboy, selling newspapers and candy on the local railroad that ran through Port Huron to Detroit. He seems to have spent much of his free time reading scientific, and technical books, and also had the opportunity at this time to learn how to operate a telegraph. By the time he was sixteen, Edison was proficient enough to work as a telegrapher full time.

The development of the telegraph was the first step in the communication revolution, and the telegraph industry expanded rapidly in the second half of the 19th century. This rapid growth gave Edison and others like him a chance to travel, see the country, and gain experience. Edison worked in a number of cities throughout the United States before arriving in Boston in 1868. Here Edison began to change his profession from telegrapher to inventor. He received his first patent on an electric vote recorder, a device intended for use by elected bodies such as Congress to speed the voting process. This invention was a commercial failure. Edison resolved that in the future he would only invent things that he was certain the public would want.

Edison moved to New York City in 1869. He continued to work on inventions related to the telegraph, and developed his first successful invention, an improved stock ticker called the 'Universal Stock Printer'. For this and some related inventions Edison was paid $40,000. This gave Edison the money he needed to set up his first small laboratory and manufacturing facility in Newark, New Jersey in 1871. During the next five years, Edison worked in Newark inventing and manufacturing devices that greatly improved the speed and efficiency of the telegraph. He also found to time to get married to Mary Stilwell and start a family.

In 1876 Edison sold all his Newark manufacturing concerns and moved his family and staff of assistants to the small village of Menlo Park, twenty-five miles southwest of New York City. Edison established a new facility containing all the equipment necessary to work on any invention. This research and development laboratory was the first of its kind anywhere; the model for later, modern facilities such as Bell Laboratories, this is sometimes considered to be Edison's greatest invention. Here Edison began to change the world.

The first great invention developed by Edison in Menlo Park was the tin foil phonograph. The first machine that could record and reproduce sound created a sensation Tinfoil phonograph, 1877and brought Edison international fame. Edison toured the country with the tin foil phonograph, and was invited to the White House to demonstrate it to President Rutherford B. Hayes in April 1878.

Edison next undertook his greatest challenge, the development of a practical incandescent, electric light. The idea of electric lighting was not new, and a number of people had worked on, and even developed forms of electric lighting. But up to that time, nothing had been developed that was remotely practical for home use. Edison's eventual achievement was inventing not just an incandescent electric light, but also an electric lighting system that contained all the elements necessary to make the incandescent light practical, safe, and economical. After one and a half years of work, success was achieved when an incandescent lamp with a filament of carbonized sewing thread burned for thirteen and a half hours. The first public demonstration of the Edison's incandescent lighting system was in December 1879, when the Menlo Park laboratory complex was electrically lighted. Edison spent the next several years creating the electric industry. In September 1882, the first commercial power station, located on Pearl Street in lower Manhattan, went into operation providing light and power to customers in a one square mile area; the electric age had begun.

Edison next undertook his greatest challenge, the development of a practical incandescent, electric light. The idea of electric lighting was not new, and a number of people had worked on, and even developed forms of electric lighting. But up to that time, nothing had been developed that was remotely practical for home use. Edison's eventual achievement was inventing not just an incandescent electric light, but also an electric lighting system that contained all the elements necessary to make the incandescent light practical, safe, and economical. After one and a half years of work, success was achieved when an incandescent lamp with a filament of carbonized sewing thread burned for thirteen and a half hours. The first public demonstration of the Edison's incandescent lighting system was in December 1879, when the Menlo Park laboratory complex was electrically lighted. Edison spent the next several years creating the electric industry. In September 1882, the first commercial power station, located on Pearl Street in lower Manhattan, went into operation providing light and power to customers in a one square mile area; the electric age had begun.

Drawing of electric light The success of his electric light brought Edison to new heights of fame and wealth, as electricity spread around the world. Edison's various electric companies continued to grow until in 1889 they were brought together to form Edison General Electric. Despite the use of Edison in the company title however, Edison never controlled this company. The tremendous amount of capital needed to develop the incandescent lighting industry had necessitated the involvement of investment bankers such as J.P. Morgan. When Edison General Electric merged with its leading competitor Thompson-Houston in 1892, Edison was dropped from the name, and the company became simply General Electric.



This period of success was marred by the death of Edison's wife Mary in 1884. Edison's involvement in the business end of the electric industry had caused Edison to spend less time in Menlo Park. After Mary's death, Edison was there even less, living instead in New York City with his three children. A year later, while vacationing at a friends house in New England, Edison met Mina Miller and fell in love. The couple was married in February 1886 and moved to West Orange, New Jersey where Edison had purchased an estate, Glenmont, for his bride. Thomas Edison lived here with Mina until his death.

When Edison moved to West Orange, he was doing experimental work in makeshift facilities in his electric lamp factory in nearby Harrison, New Jersey. A few months after his marriage, however, Edison decided to build a new laboratory in West Orange itself, less than a mile from his home. Edison possessed the both the resources and experience by this time to build, 'the best equipped and largest laboratory extant and the facilities superior to any other for rapid and cheap development of an invention '. The new laboratory complex consisting of five buildings opened in November 1887. A three story main laboratory building contained a power plant, machine shops, stock rooms, experimental rooms and a large library. Four smaller one story buildings built perpendicular to the main building contained a physics lab, chemistry lab, metallurgy lab, pattern shop, and chemical storage. The large size of the laboratory not only allowed Edison to work on any sort of project, but also allowed him to work on as many as ten or twenty projects at once. Facilities were added to the laboratory or modified to meet Edison's changing needs as he continued to work in this complex until his death in 1931. Over the years, factories to manufacture Edison inventions were built around the laboratory. The entire laboratory and factory complex eventually covered more than twenty acres and employed 10,000 people at its peak during World War One (1914-1918).

After opening the new laboratory, Edison began to work on the phonograph again, having set the project aside to develop the electric light in the late 1870s. By the 1890s, Edison began to manufacture phonographs for both home, and business use. Like the electric light, Edison developed everything needed to have a phonograph work, including records to play, equipment to record the records, and equipment to manufacture the records and the machines. In the process of making the phonograph practical, Edison created the recording industry. The development and improvement of the phonograph was an ongoing project, continuing almost until Edison's death.

Replica of original phonograph The Inventions of Thomas Edison

Phonograph – History

The first great invention developed by Edison in Menlo Park was the tin foil phonograph. While working to improve the efficiency of a telegraph transmitter, he noted that the tape of the machine gave off a noise resembling spoken words when played at a high speed. This caused him to wonder if he could record a telephone message. He began experimenting with the diaphragm of a telephone receiver by attaching a needle to it. He reasoned that the needle could prick paper tape to record a message. His experiments led him to try a stylus on a tinfoil cylinder, which, to his great surprise, played back the short message he recorded, 'Mary had a little lamb.'

The word phonograph was the trade name for Edison's device, which played cylinders rather than discs. The machine had two needles: one for recording and one for playback. When you spoke into the mouthpiece, the sound vibrations of your voice would be indented onto the cylinder by the recording needle. This cylinder phonograph was the first machine that could record and reproduce sound created a sensation and brought Edison international fame.

August 12, 1877, is the date popularly given for Edison's completion of the model for the first phonograph. It is more likely, however, that work on the model was not finished until November or December of that year, since he did not file for the patent until December 24, 1877. He toured the country with the tin foil phonograph, and was invited to the White House to demonstrate it to President Rutherford B. Hayes in April 1878.

In 1878, Thomas Edison established the Edison Speaking Phonograph Company to sell the new machine. He suggested other uses for the phonograph, such as: letter writing and dictation, phonographic books for blind people, a family record (recording family members in their own voices), music boxes and toys, clocks that announce the time, and a connection with the telephone so communications could be recorded.

Disc Phonograph – History

Photograph of Thomas A. Edison listening to the New Edison Diamond Disc Phonograph

Cylinders peaked in popularity around 1905. After this, discs and disc players, most notably the Victrolas, began to dominate the market. Columbia Records, and Edison competitor, had stopped marketing cylinders in 1912. The Edison Company had been fully devoted to cylinder phonographs, but, concerned with discs' rising popularity, Edison associates began developing their own disc player and discs in secret. Dr. Jonas Aylsworth, chief chemist for Edison, and later after his retirement in 1903, a consultant for the company, took charge of developing a plastic material for the discs. The aim was to produce a superior-sounding disc that would outperform the rivals' shellac records, which were prone to wear and warping. Another difference from competitors' discs was that the vertical-cut method was to be used for the grooves. In this manner, the stylus would bob up and down in the groove, rather than from side to side or laterally. Ten-inch records would run for 5 minutes per side at approximately 80 r.p.m.

Although Edison associates initially worked on the project in secret, when Edison discovered it, he took control of this new project and gave it much of his personal attention.

Aylsworth molded phenol and formaldehyde mixed with wood-flour and a solvent into a heat-resistant disc. This material always remained absolutely plane, which was essential as it formed the core of the disc record. A phenolic resin varnish called Condensite was applied to the core, and then the disc was stamped in the record press. The finished 10' disc weighed ten ounces, heavier than most, partially due to the 1/4' thickness of the record. A diamond point was obtained for the stylus. The Disc Phonograph and the Edison Discs were designed to be an entire system, incompatible with other discs or disc players.

The new Edison Disc Phonograph was shown for the first time publicly at the Fifth Annual Convention for the National Association of Talking Machine Jobbers at Milwaukee, Wisconsin, on July 10-13th, 1911. Press reported that the new machine was based on Edison's British 1878 patent in order to deter claims of copyright infringement with Victor or Berliner. The new machine was also mentioned in the Edison Phonograph Monthly in July of 1911, but it was over a year before disc players or discs would be offered for sale.

By the end of 1912, three basic models of the Edison Disc Phonograph had been designed, ranging in price from $150 to $250, and the company salesmen took them around the country. Soon after, the choice of models was extended to feature less expensive players and luxury machines in stylish wood cabinets. Prices for the discs started from $1.15 to $4.25, but later came down to $1.35 to $2.25. The discs were expensive to make because of the complicated chemical processes used for them.

Initial public reaction was not encouraging for several reasons. The Edison cabinets were deemed to be less attractive than the Victrolas, and customers were required to buy Edison discs only for Edison players, since they were not compatible with other players. The laminated surface of the discs also had a tendency to detach from the core material, and surface noise was frequently apparent, which contradicted the aim of perfection that the company was trying to achieve with its recordings. Still, the phonographs and discs were touted as being acoustically better than those of the competitors. In order to bolster claims of superiority, Edison claimed that his records could be played 1,000 times without wear

Recitals were also conducted to prove the merit of the discs. Edison recording artists would sing along with a disc recording of their voices, daring the audience to be able to tell the difference. In late 1915, Edison began its famous Tone Tests, which featured artists alternating their live performance on a darkened stage with that on the disc in front of large audiences, challenging them to detect a difference. Reaction was positive to these tests, and reinforced the Edison motto that the discs were 're-creations' of performances, not merely recordings of them.




Additional advertising for the Diamond Disc was secured through promotion of the Edison film The Voice of the Violin, made in 1915, which featured a Tone Test by Anna Case. (The Library of Congress copy is incomplete and, unfortunately, is lacking Case's performance.)

On the disc label, sides were indicated by 'L' and 'R', referring to the left side or the right side when stored vertically. The early disc issues contained the Edison trademark, Edison's image, the title of the selection, and the composer, all pressed into the glossy black surface of the disc using a half-tone electrotype. The early issues did not carry the artists' names, reflecting Edison's policy of not seeking out name acts, but supposedly relying on the quality of the music alone. In 1915, the artists' names began to be added to the labels. In 1921, black paper labels with white Roman type began to be used, and were changed at the end of 1923 to white labels.

By 1916, demand increased for console cabinets to house the disc players. The Edison Company produced a series of period models to compete with those of the Victor Company. The designer for the cabinets was H.D. Newson from the W.A. French Furniture Company of Minneapolis. Named 'The Art Models,' these cabinets came in English, French, and Italian period styles, as well as Gothic styles. Prices ranged from $1,000 to $6,000. Advertising for these models made it clear that the players themselves were the same as lower-priced models; the inflated cost was for the cabinet.

In 1917 when the U.S. became involved in World War I, the Edison Company created the Army and Navy Model in answer to a request for machines from the United States Army

Depot Quartermaster in New York. The simple, basic machine sold for $60. The Department of War never purchased any, but individual units bought them, some taking them overseas. The Army and Navy Model was discontinued after the war's end.

By 1917, the Disc Phonograph had garnered considerable success in the marketplace. This good fortune continued for almost seven years. In contrast, the cylinder phonograph business declined; by 1925, the remaining cylinder customers had to order directly from the factory. By 1920, Edison was the only disc company not using steel needles or the lateral method of grooves.

By 1924, business began to sour with the advent of competition from radio. Operations were cut back, and experimentation began with long-playing records. These were introduced in October 1926 along with four new console disc phonographs. As a concession to the marketplace, attachments were also offered so that the Edison phonographs could play the laterally-cut records of competitors.

By the latter half of the 20's, the company started to diversify its interests in an attempt to stay viable. Thoughts of moving pictures with sound led the company to develop an Ediscope which featured still pictures with narration. This was envisioned as being appropriate for the children's market, since it could be used for fairy tales and educational nature talks. Work was also begun on the Cine-Music Phonograph, which was conceived to supply musical accompaniment to motion pictures.

Edison entered into the radio business in 1928 by taking over the Aplitdorf-Bethlehem Electrical Company of Newark, a move which allowed him to produce radio-phonographs. The Edison Company further expanded into the field of radio by making programs for radio on long-playing discs. Radio station WAAM of Newark, NJ, agreed to use the new Rayediphonic Reproducing Machine and Radiosonic records in 1929, with the first Radiosonic broadcast being aired on April 4. It appeared that the company had finally found a profitable outlet.

In the summer of 1929, the Edison company gave into the popular trend and introduced the Edison Portable Disc Phonograph with New Edison Needle Records, offering both the Diamond Discs and the new needle records simultaneously.

These changes did not measurably improve business, and on October 21, orders were given to close the Edison disc business, with the company stating that it would focus on the manufacture of its radio-phonographs in the future.

Kinetophones – History

Frames from early experimental attempt to create sound motion pictures by the Edison Manufacturing Company show Kinetophones in action

From the inception of motion pictures, various inventors attempted to unite sight and sound through 'talking' motion pictures. The Edison Company is known to have experimented with this as early as the fall of 1894 under the supervision of W. K. L. Dickson with a film known today as Dickson Experimental Sound Film. The film shows a man, who may possibly be Dickson, playing violin before a phonograph horn as two men dance.

By the spring of 1895, Edison was offering Kinetophones--Kinetoscopes with phonographs inside their cabinets. The viewer would look into the peep-holes of the Kinetoscope to watch the motion picture while listening to the accompanying phonograph through two rubber ear tubes connected to the machine (the kinetophone). The picture and sound were made somewhat synchronous by connecting the two with a belt. Although the initial novelty of the machine drew attention, the decline of the Kinetoscope business and Dickson's departure from Edison ended any further work on the Kinetophone for 18 years.

In 1913, a different version of the Kinetophone was introduced to the public. This time, the sound was made to synchronize with a motion picture projected onto a screen. A celluloid cylinder record measuring 5 1/2' in diameter was used for the phonograph. Synchronization was achieved by connecting the projector at one end of the theater and the phonograph at the other end with a long pulley.

Nineteen talking pictures were produced in 1913 by Edison, but by 1915 he had abandoned sound motion pictures. There were several reasons for this. First, union rules stipulated that local union projectionists had to operate the Kinetophones, even though they hadn't been trained properly in its use. This led to many instances where synchronization was not achieved, causing audience dissatisfaction. The method of synchronization used was still less than perfect, and breaks in the film would cause the motion picture to get out of step with the phonograph record. The dissolution of the Motion Picture Patents Corp. in 1915 may also have contributed to Edison's departure from sound films, since this act deprived him of patent protection for his motion picture inventions.

Electricity and Lightbulb - History

Replica of original lightbulb - patent # 223,898 Thomas Edison's greatest challenge was the development of a practical incandescent, electric light. Contrary to popular belief, he didn't 'invent' the lightbulb, but rather he improved upon a 50-year-old idea. In 1879, using lower current electricity, a small carbonized filament, and an improved vacuum inside the globe, he was able to produce a reliable, long-lasting source of light. The idea of electric lighting was not new, and a number of people had worked on, and even developed forms of electric lighting. But up to that time, nothing had been developed that was remotely practical for home use. Edison's eventual achievement was inventing not just an incandescent electric light, but also an electric lighting system that contained all the elements necessary to make the incandescent light practical, safe, and economical. After one and a half years of work, success was achieved when an incandescent lamp with a filament of carbonized sewing thread burned for thirteen and a half hours.

There are a couple of other interesting things about the invention of the light bulb: While most of the attention was on the discovery of the right kind of filament that would work, Edison actually had to invent a total of seven system elements that were critical to the practical application of electric lights as an alternative to the gas lights that were prevalent in that day.

These were the development of: 

  1. the parallel circuit, 
  2. a durable light bulb, 
  3. an improved dynamo, 
  4. the underground conductor network, 
  5. the devices for maintaining constant voltage, 
  6. safety fuses and insulating materials, and 
  7. light sockets with on-off switches. 

Before Edison could make his millions, every one of these elements had to be invented and then, through careful trial and error, developed into practical, reproducible components. The first public demonstration of the Thomas Edison's incandescent lighting system was in December 1879, when the Menlo Park laboratory complex was electrically lighted. Edison spent the next several years creating the electric industry.



The modern electric utility industry began in the 1880s. It evolved from gas and electric carbon-arc commercial and street lighting systems. On September 4, 1882, the first commercial power station, located on Pearl Street in lower Manhattan, went into operation providing light and electricity power to customers in a one square mile area; the electric age had begun. Thomas Edison's Pearl Street electricity generating station introduced four key elements of a modern electric utility system. It featured reliable central generation, efficient distribution, a successful end use (in 1882, the light bulb), and a competitive price. A model of efficiency for its time, Pearl Street used one-third the fuel of its predecessors, burning about 10 pounds of coal per kilowatt hour, a 'heat rate' equivalent of about 138,000 Btu per kilowatt hour. Initially the Pearl Street utility served 59 customers for about 24 cents per kilowatt hour. In the late 1880s, power demand for electric motors brought the industry from mainly nighttime lighting to 24-hour service and dramatically raised electricity demand for transportation and industry needs. By the end of the 1880s, small central stations dotted many U.S. cities; each was limited to a few blocks area because of transmission inefficiencies of direct current (dc).

The success of his electric light brought Thomas Edison to new heights of fame and wealth, as electricity spread around the world. His various electric companies continued to grow until in 1889 they were brought together to form Edison General Electric. Despite the use of Edison in the company title however, he never controlled this company. The tremendous amount of capital needed to develop the incandescent lighting industry had necessitated the involvement of investment bankers such as J.P. Morgan. When Edison General Electric merged with its leading competitor Thompson-Houston in 1892, Edison was dropped from the name, and the company became simply General Electric.

Edison Motion Pictures – History

Kinetoscope - Motion Pictures Projector

Thomas Edison's interest in motion pictures began before 1888, however, the visit of Eadweard Muybridge to his laboratory in West Orange in February of that year certainly stimulated his resolve to invent a camera for motion pictures. Muybridge proposed that they collaborate and combine the Zoopraxiscope with the Edison phonograph. Although apparently intrigued, Edison decided not to participate in such a partnership, perhaps realizing that the Zoopraxiscope was not a very practical or efficient way of recording motion. In an attempt to protect his future, he filed a caveat with the Patents Office on October 17, 1888, describing his ideas for a device which would 'do for the eye what the phonograph does for the ear' -- record and reproduce objects in motion. He called it a 'Kinetoscope,' using the Greek words 'kineto' meaning 'movement' and 'scopos' meaning 'to watch.'

One of Edison's first motion picture and the first motion picture ever copyrighted showed his employee Fred Ott pretending to sneeze. One problem was that a good film for motion pictures was not available. In 1893, Eastman Kodak began supplying motion picture film stock, making it possible for Edison to step up the production of new motion pictures. He built a motion picture production studio in New Jersey. The studio had a roof that could be opened to let in daylight, and the entire building was constructed so that it could be moved to stay in line with the sun.

C. Francis Jenkins and Thomas Armat invented a film projector called the Vitascope and asked Edison to supply the films and manufacture the projector under his name. Eventually, the Edison Company developed its own projector, known as the Projectoscope, and stopped marketing the Vitascope. The first motion pictures shown in a 'movie theater' in America were presented to audiences on April 23, 1896, in New York City.

The Failed Inventions

Thomas Alva Edison sits between two phonograph cabinets

Thomas Alva Edison held 1,093 patents for different inventions. Many of them, like the lightbulb, the phonograph, and the motion picture camera, were brilliant creations that have a huge influence on our everyday life. However, not everything he created was a success; he also had a few failures.

One concept that never took off was Edison's interest in using cement to build things. He formed the Edison Portland Cement Co. in 1899, and made everything from cabinets (for phonographs) to pianos and houses. Unfortunately, at the time, concrete was too expensive and the idea was never accepted. Cement wasn't a total failure, though. His company was hired to build Yankee Stadium in the Bronx.

W.K.L. Dickson From the beginning of the creation of motion pictures, many people tried to combine film and sound to make 'talking' motion pictures. Here you can see to the left an example of an early film attempting to combine sound with pictures made by Edison's assistant, W.K.L. Dickson. By 1895, Edison had created the Kinetophone--a Kinetoscope (peep-hole motion picture viewer) with a phonograph that played inside the cabinet. Sound could be heard through two ear tubes while the viewer watched the images. This creation never really took off, and by 1915 Edison abandoned the idea of sound motion pictures.

Thomas Alva Edison sitting at the door of the ore-milling plant in New Jersey The greatest failure of Thomas Edison's career was his inability to create a practical way to mine iron ore. He worked on mining methods through the late 1880s and early 1890s to supply the Pennsylvania steel mills' demand for iron ore. In order to finance this work, he sold all his stock in General Electric, but was never able to create a separator that could extract iron from unusable, low-grade ores. Eventually, Edison gave up on the idea, but by then he had lost all the money he'd invested.

Conclusion

Thomas Alva Edison was a man who influenced America more than anyone else. He became throw his inventions one of the most important figures that world knew. His name is immortal threw ages just because his brilliant mind .

He was lucky because he was a businessman too, and he could start the production of all his invention which help us nowadays. Beside all this he ruined the hopes of others peoples to try to assume the same inventions , as we can say now he registered these devices with the original brand no copyright allowed.

In my opinion, Thomas Edison was a person who deserves our respect for his influence on political thought and for the long-lasting effects of all that he accomplished during his long and fruitful career.

Bibliography

Books (information)

1. Edison: The man who made the future by Ronald W. Clark

2. Edison: Inventing the Century by Neil Baldwin

3. Edison by Matthew Josephson. McGraw Hill



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