Current Affairs Science Projects And Inventions

German scientist Carl von Linde (1842-1934) first invented a way to turn gases into liquid. His discovery would form the basis of modern refrigeration and liquid air production. From the 1600s scientists had known that temperature affects whether a substance is in a gaseous or liquid state. By cooling and pressurizing a gas, it is possible to slow the molecules down and compress them until they collapse and form a liquid. French mathematician Gaspard Monge first produced liquid sulfur dioxide in 1784, and by the late 1800s most gases had been successfully liquefied. However, it was still not possible to produce large quantities suitable for commercial use. Von Linde had the bright idea of using air itself as a coolant. In 1894, in response to a request from the Guinness brewery in Dublin, Ireland, to create a new refrigeration system, von Linde succeeded in liquefying air by first compressing it and then letting it expand quickly, causing it to cool. The cold air was constantly recycled to cool more incoming air until eventually the gas liquefied. The "Linde technique" allowed the continuous production of large quantities of liquid gases such as oxygen and nitrogen, and became an immediate commercial success. The biggest use of liquid oxygen was initially for the oxyacetylene torch, invented in France in 1904 and used for cutting and welding metal. This revolutionized the construction of ships, skyscrapers, and other ironworks during the early twentieth century. Later applications of liquefaction of air included liquid oxygen for distribution to hospitals and industries, and liquid nitrogen for cooling blood and tissues in biological applications. 

"Well, it was kind of an accident, because plastic is not what I meant to invent." Leo Baekeland, Belgian-American chemist A few lucky individuals change history and, at the same time, make a lot of money. Such was the case with Belgian-born Leo Hendrik Baekeland (1863-1944), who proved to have a keen eye for opportunity and the drive and know-how to see a project to fruition. Baekeland's first major invention was a dramatic improvement in photographic paper. Eastman Kodak purchased his invention (dubbed "Velox") for upwards of three-quarters of a million dollars in-1898. Freed from financial worry, Baekeland then had his days free to experiment in his laboratory. As the electronics industry grew in the late nineteenth and early twentieth centuries, so did the demand for insulators. Greatly in demand at this time was shellac, a natural product made from a beetle indigenous to Asia. It also turned out to be a great insulator. Baekeland realized that given its high demand and limited supply, synthetic shellac would be a goldmine. By mixing carbolic acid and formaldehyde in a controlled environment, Baekeland soon created a product that could be painted onto a surface, just like shellac, or be molded into almost any shape or form. The product, named Bakelite, was the first totally synthetic plastic and the forefather of the same product that is used today in bottles, computer keyboards, light switches, and countless other everyday products. 

Few other names are as synonymous with invention and innovation in the field of munitions and weapons as that of the Maxim family. This remarkably inventive family's output was not exclusively weapon-related. Indeed, Hiram Percy Maxim's (1869-1936) creation—which enabled a firearm to be discharged without the traditional loud bang—initially stemmed from his interest in automobile design, specifically exhaust silencers or "mufflers." The bulk of noise produced by a firearm discharging subsonic ammunition is caused by a massive and rapid expansion of propellant gases leaving the muzzle, a bit like uncorking a bottle of fizzy champagne. Maxim's silencer—which, like all such devices, suppresses rather than truly silences— attaches to the barrel of a firearm. Essentially a cylindrical casing of much larger capacity than the barrel, and containing a series of baffles, it allows the explosive gases from the cartridge to expand and slow prior to hitting the surrounding air, producing far less noise. Muzzle flash is also reduced. First designed around 1902 and patented in 1909, a unique feature of the Maxim unit was that it was not concentric to the bore, as are the majority of today's silencers, but was offset to allow the use of the original weapon sights without modification. Maxim's silencer was marketed quite creatively as a gentlemanly way of target shooting. Although it was later adopted by police and military forces across the world for use on a variety of weapons, fears were expressed at the time that the availability of a "noiseless weapon" could prove a major boon to criminals and gangsters. 

It was at the 1900 Paris Exposition that the first public demonstration of sound and vision in a movie theater took place. However, projecting volume into a large auditorium was difficult at a time when amplified public address systems did not yet exist; furthermore, the crude synchronization of sound and vision was simply a case of starting the movie projector and audio playback cylinder at the same moment and hoping for the best. Low-key experimentation continued over the next two decades until, in 1919, electrical engineer Lee De Forest (1873-1961) developed the first sound-on-film technology: a system where a soundtrack "strip" was added to the movie film. Four years later, on April 23, 1923, De Forest's Phonofilms studio was responsible for the first public screening of a fully synchronized talking picture. A year later he made the first commercial dramatic talking picture, Love's Old Sweet Song, directed by H. Manning Haynes and starring John Stuart and Joan Wyndham. There was anxiety within Hollywood, however, that this new technology would threaten their dominant position at the heart of what was now a multi-million- dollar industry. Furthermore, a number of major Hollywood studios began developing their own competing, incompatible technologies. It took the success in 1927 of The Jazz Singer, directed by Alan Crosland, to prove that talking pictures could yield great profitability—even if this success was more down to its star, Al Jolson, being one of America's biggest celebrities than any public desire to experience synchronized sound and image. Nonetheless, the major studios gradually began to back the idea, and by 1930 the era of the silent movie was all but over. 

At the end of the 1960s, Intel's Ted Hoff (b. 1937) was asked to design several different calculators for a Japanese client. The traditional way would have been to develop several different integrated circuits—silicon chips—to do the work. Even though these were small enough to be put into handheld calculators, programmable computers, which could do a variety of jobs, were still huge devices. Combining the small size of integrated circuits with the power of programmable computers was an inevitable idea. Hoff decided that he would make a single integrated circuit that could be programmed to do many different things. Joined by fellow engineers Stan Mazor (b. 1941) and Federico Faggin (b. 1941), Hoff squeezed an entire computer onto a single silicon chip, pairing it with a small memory to give it its instructions. His range of calculators all used the same chip, but each one had different instructions to instruct it how to behave. Intel quickly realized that they had, quite literally in the palms of their hands, a programmable, general- purpose computer with the power of machines that a decade before had taken up entire rooms. Making a deal with the calculator manufacturer, Intel kept the rights to sell the chip to other people and released the Intel 4004 processor in 1971. The 4004, the first commercial microprocessor, was also the first step in the revolution that would sweep the world during the 1970s and 1980s, taking computers from their air-conditioned industrial servitude and bringing them to homes, cars, and even washing machines. 

“... if you are not working on important things, you are wasting time." Dean Kamert The insulin pump is a small, battery-powered device that releases varying amounts of insulin into the bloodstream of diabetics. Diabetes is a disease that affects the body's ability to break down sugar, caused by an absence or insensitivity to the hormone insulin. Until the invention of the insulin pump, the only way for diabetics to control their disease was to inject themselves daily with insulin. The first insulin pump was invented by Dr. Arnold Kadish in the 1960s, but it was so large it had to be worn like a backpack. While Dean Kamen (b. 1951) was at college, his brother, then a medical student , approached him with a problem. He complained that there was no way to provide patients with steady doses of drugs, such as insulin. In response, Kamen constructed a circuit that controlled a small pump of insulin connected to a syringe. He used a new form of microchip—which did not require much power—to control the circuit. The device was wearable and programmable and delivered small, precise doses of insulin over a long period of time, evening out the peaks and troughs of insulin levels associated with injections. Kamen's brother showed this device to his colleagues and they were immediately impressed. In 1976, Kamen founded his first company, Auto Syringes Inc., to market and manufacture the pumps. 

"It [radiant matter] is projected with great velocity from the negative pole." William Crookes, English chemist and physicist The mid- to late-1800s was a period of scientific revolution with physical processes such as electricity beginning to reveal their secrets. Early investigations into electricity led to the development of the cathode ray tube, which would eventually lead to the discovery of the electron, as well as to the invention of television. Michael Faraday (1791-1867) noticed that after removing most of the air in a glass tube containing a cathode and anode, a faint glow could be seen between the positive and negative electrodes. Faraday's work was limited initially by the inability to create more than a partial vacuum. Around 1855 German scientists Heinrich Geissler and Julius Plucker improved vacuum technology and were able to remove more of the airfrom inside such a tube. With the improved vacuum, Plucker was able to produce a much brighter glow between the electrodes. He was also able to demonstrate that the glow responded to the effects of a magnetic field. English chemist and physicist William Crookes (1832-1919) had already made significant discoveries before he turned his attention to vacuum tubes. Using his Crookes tubes, which created an even better vacuum than those of Geissler and Plucker, he showed that the "cathode rays" that cause the glow traveled in straight lines, causing phosphorescence upon striking certain materials. Crookes also installed tiny vanes that would turn in the tubes as the current was applied. He thought he had discovered a fourth state of matter— "radiant matter"—but the true nature of this phenomenon had to wait until J. J. Thompson's studies showed these particles to be subatomic. 

A sword consists of a blade and a handle, which is itself made up of a hilt, or grip, and a pommel, or counterweight. A sword blade has one or two edges for striking and cutting, and a point for thrusting. The word "sword" comes from the Old English sweord, meaning to wound or hurt. Humans developed weapons from sharpened flint tools, and in the Bronze Age short-bladed weapons such as daggers were used. It was then impractical to make bronze swords more than 3 feet (90 cm) long, but with the development of smelting technology and stronger alloys, longer iron swords became possible from about 1500 B.C.E. The Chinese single-edged steel sword appeared in the third century B.C.E. By Roman times the hilt was distinct from the short, flat blade, and by the European Middle Ages the sword had acquired its main basic shape and a variety of designs were devised to fulfill different functions. Medieval swords had a double- edged blade, a large hilt, and protective guard and were designed to be gripped in both hands. A curved blade for cutting, used in Asia, was introduced into Europe by the Turks in the sixteenth century, and in the West was modified into the cavalry saber. Hunting swords and the naval cutlass developed from the sixteenth-century "hanger," with its convex cutting edge, as did the bayonet, developed in the seventeenth century for use with firearms. During the seventeenth and eighteenth centuries, the shorter "smallsword" became a fashion accessory. The smallsword and the rapier remained popular dueling swords well into the eighteenth century. 

"The object of my invention adapt it to sweeping carpets and floors with uneven surfaces..." Melville Bissell In the nineteenth century, the large Turkish or Axminster carpets that covered floors were not easily cleaned. They had to be taken outside and beaten vigorously with a rug beater to remove the dust. American Melville Bissell (1843-1889) and his wife Anna noticed that the dust in their carpets irritated her and adversely affected his health. To alleviate the dust problem, Melville designed a long-handled carpet sweeper with rotating bristles that bent as they scooped up dirt from a carpet, then flicked it into a compartment Inside the device. The rotation was powered by the sweeper's movement across the floor, and the head could be adjusted to clean bare floors, carpets, rugs, and uneven surfaces. News of the Bissell sweeper spread. Local women began to manufacture the bristles at home and the sweepers were assembled in the shop before being sold door-to-door. He patented his design in 1876 and opened his first manufacturing plant in Grand Rapids in 1883 The company expanded internationally and had its big break in Britain after Queen Victoria allowed her palace carpets to be "Bisselled." The advent of the home electrical vacuum cleaner saw sales of carpet sweepers gradually decline and the Bissell sweeper, although still available today as a rechargeable, motorized variant, has been relegated to something of a novelty item. 

Although hearing aids have probably been around for centuries, they are first mentioned in Giambattista della Porta's Magia Naturalis (1598). These early devices were made from wood and were carved to resemble the ears of anil-mils known to have acute hearing. By the late 1700s, ear trumpets were widely available in an array of different shapes, sizes, and materials. These devices all served to passively gather sound waves and direct them to the ear canal. However, in 1819 F.C. Rein made an acoustic throne for King Goa of Portugal. It had carved lions' heads for arm rests and concealed in the heads were resonating chambers that led to a hearing tube by the king's head. In the 1890s there were numerous attempts to develop a powered hearing aid, using the recently invented storage battery. The first commercially successful powered hearing aid was the "Akoulallion" developed in 1898 by Dr. Miller Reese Hutchison (1876-1944), and patented in 1899. This early model was bulky, being designed to sit on a tabletop, and very expensive. Battery life was very limited, as was the range of frequencies. It produced only modest amplification, restricting it to those with only mild to moderate hearing loss. In 1902, he traveled to London and presented a model to Queen Consort Alexandra, who was becoming hard of hearing. By 1903, he had developed the portable "Acousticon." Hutchison is also known for developing the electric klaxon horn, which saw widespread use in early automobiles. This has led some to quip that he invented the horn to deafen people so they would have to buy more Acousticons.