It is used in mirror production and may be deposited on glass or metals by chemical deposition, electrode position, or by evaporation. When freshly deposited, it is the best reflector of visible light known, but is rapidly tarnished and loses much of its reflectance. It is a poor reflector of ultraviolet. Silver fulminate, a powerful explosive, is sometimes formed during the silvering process. Silver iodide is used in seeding clouds to produce rain. Silver chloride has interesting optical properties as it can be made transparent; it also is a cement for glass.
Silver nitrate, or lunar caustic, the most important silver compound, is used extensively in photography. For centuries silver has been used traditionally for coinage by many countries of the world.
In recent times, however, consumption of silver has greatly exceeded the output. While silver itself is not considered to be toxic, most of its salts are poisonous. Silver compounds can be absorbed in the circulatory system and reduced silver deposited in the various tissues of the body. A condition, known as argyria, results with a grayish pigmentation of the skin and mucous membranes. Silver has germicidal effects and kills many lower organisms effectively without harm to higher animals.
In , the price of silver was fixed by the U. In November the U. The coinage act of authorized a change in the metallic composition of the three U. This was the first change in U. Silver coins of other countries have largely been replaced with coins made of other metals. On Jun. Government ceased to redeem U. Silver Certificates with silver. Since that time, the price of silver has fluctuated widely. A particle accelerator is a device that uses electric fields to propel electrically charged particles to high speed.
These high speed particles contain high energy. Particles accelerated by particle accelerator to high energy can be used to bombard target elements for conducting experiments. This is called particle bombardment technique. Nuclear fusion is the process by which multiple nuclei join together to form a heavier nucleus. It is accompanied by the release or absorption of energy depending on the masses of the nuclei involved.
Cold fusion is a nuclear fusion process that occurs at normal temperature. The main object of the present invention is to provide a man made method to produce silver, which has high market value. Another object of the present invention is to man made silver by using particle bombardment technique.
Another object of the present invention is to man made silver by utilizing particle accelerator to accelerate Boron particles to high speed. At very low temperatures, superconductors carry electricity with little or no electrical resistance. They can be used to generate magnetic energy for turning motors or propelling magnetic levitation trains.
The myriad applications of silver in electronics offer an eye-opening view into how one of the most famous metals in history has become a cutting edge material of the future. Due in part to its unique property of having the highest thermal and electrical conductivity of all metals, silver is often a must-have over other, less expensive materials. Silver in solar panels: Silver paste contacts form bus bars and grid lines that draw electrical current from the semiconducting surface of a photovoltaic cell.
As mentioned previously, silver paste is used to make solar panels. Silver paste contacts printed onto photovoltaic cells capture and carry electrical current. This current is produced when energy from the sun impacts the semiconducting layer of the cell. Photovoltaic cells are one of the fastest growing uses of silver.
Silver's reflectivity gives it another role in solar energy. It reflects solar energy into collectors that use salts to generate electricity. Nuclear energy also uses silver. The white metal is often employed in control rods to capture neutrons and slow the rate of fission in nuclear reactors. Inserting the control rods into the nuclear core slows the reaction, while removing them speeds it up. Silver brazing and soldering: Silver brazing and soldering ensures a tight joint between metal pipes.
Brazing and soldering make use of silver's high tensile strength and ductility to create joints between two metal pieces. Silver scrap can be used in brazing and soldering because these processes do not require very pure silver. Brazing and soldering produce tight joints for everything from heating and air conditioning vents to plumbing. Silver's antibacterial properties and non-toxicity to humans make it a great replacement for lead-based bonds between water pipes.
Silver wire: Silver wire can be woven into a metal mesh and used as a catalyst. Granular silver also makes a good catalyst. Silver acts as a catalyst to produce two important chemicals: ethylene oxide and formaldehyde. Ethylene oxide is used to produce molded plastics, such as plastic handles, and flexible plastics, such as polyester. It is also a major ingredient in antifreeze.
Formaldehyde is used to make solid plastics and resins and as a protective coating. It is also used as a disinfectant and embalming agent. As a catalyst, silver increases the speed of reactions without getting used up. Silver coins and bullion: Silver coins have been minted for thousands of years. Silver bullion is still a popular investment choice today. Related: The Many Uses of Gold. Silver has traditionally served, with gold, as the metal used in coins.
As a precious metal, silver is rare and valuable, making it a convenient store of wealth. In the past, people accumulated their wealth in the form of silver coins; today, they invest in investment-grade silver bullion.
The fact that silver does not corrode and only melts at a relatively high temperature, means that it can last, and the fact that it has high luster makes it attractive. Its malleability makes silver a good choice for designing and minting local currency.
In greater abundance, and therefore less expensive, than gold, silver has been used more prevalently as currency. Silver was mined and used in trading several thousands of years BC and was first minted into silver coins in the Mediterranean region many hundreds of years BC.
Until the 20th century, many countries used a silver or gold standard, backing up the value of currency with the presence of gold or silver in the treasury. Today, countries use less expensive metals, such as copper and nickel, to produce coins, and they use fiat currency, in which government regulation controls the value, instead of a gold or silver standard.
Still, silver retains its value as a commodity. Many individuals choose to invest in silver through financial instruments, like stocks and mutual funds, or by actually buying and storing Countries sometime produce silver collector's edition coins, which they sell to buyers at a price exceeding the value of the silver used to make the coin. Silver rings: Silver, precious and lustrous, makes beautiful, long-lasting jewelry.
Jewelry and silverware are two other traditional uses of silver. Malleability, reflectivity, and luster make silver a beautiful choice. Because it is so soft, silver must be alloyed with base metals, like copper, as in the case of sterling silver Even though it resists oxidation and corrosion, silver can tarnish, but with a little polish, it can shine for a lifetime.
Because it is less expensive than gold, silver is a popular choice for jewelry and a standard for fine dining. Silver-plated base metals offer a less costly alternative to silver.
Silver dishes and plates may accompany silverware, and these can often be ornately crafted works of art. For example, Paul Revere , known to most for his midnight ride at the start of the American Revolution, was a silversmith by trade, and some of his artwork is still on display at the Boston Museum of Fine Arts.
Silver in photography film: Silver halide in photographic film responds to light, leaving a latent image behind. Photography had been one of the primary industrial uses of silver until the recent rise of digital media.
Traditional film photography relies on the light sensitivity of silver halide crystals present in film. When the film is exposed to light, the silver halide crystals change to record a latent image that can be developed into a photograph.
The accuracy of this process makes it useful for non-digital consumer photography, film, and X-rays. The silver used in film photography should not be confused with the "silver screen" of cinema. This phrase refers not to the silver in the film itself, but to the silver lenticular screen onto which early films were projected. This is because solid silver is almost completely biologically inert, and even if ingested, would pass through the human body without being absorbed into tissues.
In very high doses — such as those a factory worker might encounter in an accident — or from prolonged exposure to silver dust or fumes, silver can have some mostly mild effects on health. For example, inhaling silver fumes or dust may irritate mucous membranes or the upper respiratory tract. Occasionally, sensitive individuals suffer allergic reactions — contact dermatitis or eye irritation — after exposure to powdered silver, silver solutions or dental fillings.
Similarly, skin creams containing silver compounds silver nitrate and silver sulphadiazine cause local skin discoloration in certain sensitive individuals.
Ingesting silver compounds, such as in medicines, can sometimes irritate the stomach. Prolonged exposure to silver dust or to the silver compounds in medicines or supplements can also result in a permanent blue-gray staining of the eyes, nose, mouth, throat and skin.
Once a person turns blue from argyria, the skin coloring is unfortunately permanent. Most medical professionals believe argyria is the most serious known health effect of silver on humans. Aside from its permanent cosmetic effect, argyria is not believed to pose any other risk to human health.
The mild, observed human health effects of silver exposure appear to be highly variable from one person or situation to another. Scientists have not identified exposure levels that can be generalized as harmful. People who are most vulnerable to minor health effects from silver including allergic contact dermatitis, or irritation of the eyes, mucous membranes, upper respiratory tract irritation, or the stomach are those who work in factories where silver is manufactured into electrical or photography equipment, with fumes or dust resulting.
Others who may be exposed to elevated levels of silver are those who work with silver in melting, casting, grinding, polishing or etching operations. In factory environments where high exposures to silver dust or fumes are likely, protective clothing, gloves, eye goggles and ventilators or respirator equipment can prevent ill effects.
There are laboratory tests that can measure silver levels in blood, urine, feces or tissues accurately and reliably. Blood or urine samples are the easiest tests to conduct, and these tests measure recent exposures — those occurring within the past week or so. For past exposures, laboratory tests can measure how much silver has built up in the skin. Although these tests can show whether a person has been exposed to silver, they cannot predict whether any ill health effects will occur.
On a practical level, tests are not generally recommended except for industrial workers who inhale or ingest silver fumes or dust to the point of experiencing symptoms such as skin or eye irritation or discoloration, irritation of the stomach, mucous membranes or upper respiratory tract. In its pure metal form or in ores, silver does not dissolve and is not considered an environmental risk.
But high doses of certain compounds of silver have been found to highly toxic to aquatic life forms, such as fish. Scientists once believed that metals that existed as free ions were most likely to pose a risk to living things, since these forms tend to react more readily with biological molecules.
Studies of fish and zooplankton exposed to high doses of silver nitrate a form of the metal containing large quantities of free ions confirmed that silver in this form is indeed highly toxic to aquatic creatures. Similar effects were found in tiny aquatic animals called zooplankton. Though these effects are dramatic, this ionic form of silver is rarely found outside a laboratory.
Scientists now suspect that lower doses of silver compounds over longer periods of time may have more subtle but equally worrisome effects on fish and other aquatic organisms — affecting the reproductive system in sensitive species.
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