Aluminium or aluminum is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, nonmagnetic, ductile metal, Aluminium metal is so chemically reactive that native specimens are rare and limited to extreme reducing environments. Instead, it is combined in over 270 different minerals. The chief ore of aluminium is bauxite, Aluminium is remarkable for the metals low density and its ability to resist corrosion through the phenomenon of passivation. Aluminium and its alloys are vital to the industry and important in transportation and structures, such as building facades. The oxides and sulfates are the most useful compounds of aluminium, despite its prevalence in the environment, no known form of life uses aluminium salts metabolically, but aluminium is well tolerated by plants and animals. Because of these salts abundance, the potential for a role for them is of continuing interest. Aluminium is a soft, lightweight, ductile. It is nonmagnetic and does not easily ignite, a fresh film of aluminium serves as a good reflector of visible light and an excellent reflector of medium and far infrared radiation.
The yield strength of aluminium is 7–11 MPa, while aluminium alloys have yield strengths ranging from 200 MPa to 600 MPa. Aluminium has about one-third the density and stiffness of steel and it is easily machined, cast and extruded. Aluminium atoms are arranged in a cubic structure. Aluminium has an energy of approximately 200 mJ/m2. Aluminium is a thermal and electrical conductor, having 59% the conductivity of copper. Aluminium is capable of superconductivity, with a critical temperature of 1.2 kelvin. Aluminium is the most common material for the fabrication of superconducting qubits, the strongest aluminium alloys are less corrosion resistant due to galvanic reactions with alloyed copper. This corrosion resistance is reduced by aqueous salts, particularly in the presence of dissimilar metals. In highly acidic solutions, aluminium reacts with water to form hydrogen, primarily because it is corroded by dissolved chlorides, such as common sodium chloride, household plumbing is never made from aluminium
State of Vietnam
The State of Vietnam was a state that claimed authority over all of Vietnam during the First Indochina War although part of its territory was actually controlled by the communist Viet Minh. The state was created in 1949 and was recognized in 1950. Former emperor Bảo Đại was chief of state, after the 1954 Geneva Agreements, the State of Vietnam had to abandon the Northern part of the country to the Democratic Republic of Vietnam. Ngô Đình Diệm was appointed prime minister that same year, and after ousting Bảo Đại in 1955, since the August Revolution, Viet Minh had seized all of the territories of Vietnam. The Democratic Republic of Vietnam was established by Viet Minh on September 2,1945, by February 1947, following the pacification of Tonkin, the Tonkinese capital and the main traffic axis returned under French control. The Việt Minh partisans were forced to retreat into the jungle, bao Dai had voluntarily abdicated on August 25,1945, after the fall of the short-lived Empire of Vietnam, a puppet state of the Empire of Japan.
However, the Democratic Republic of Vietnam had declared the independence of Vietnam and had control almost Vietnams territory since September 2,1945, besides that, the DRV had hosted the 1946 Vietnamese National Assembly election with the participation of 89% voter in Vietnam. The Democratic Republic of Vietnam, had become the constitutional representatives of Vietnam in 1946. On May 20,1949, the French National Assembly approved the reunification of Cochinchina with the rest of Vietnam, on decision took effect on June 14 and the State of Vietnam was officially proclaimed on July 2. From 1949 to 1954, reunification with Cochinchina, the State of Vietnam had partial autonomy from France as a state within the French Union. The State of Vietnam found support in the French Fourth Republic and the United States while Hồ Chí Minh was backed by the Peoples Republic of China, despite French support, roughly 60% of Vietnamese territory was under Việt Minh control in 1952. The massive voluntary migration of anti-Communist north Vietnamese, essentially Roman Catholic people, on June 14,1949, Bảo Đại was appointed Chief of State of the State of Vietnam, he was concurrently Prime Minister for a short while.
On October 26,1955, the Republic of Vietnam was established, the State of Vietnam referendum of 1955 determined the future regime of the country. Following the signing of the 1949 Élysée Accords in Paris, Bảo Đại was able to create a National Army for defense purposes and it fought under the State of Vietnams banner and leadership and was commanded by General Nguyễn Văn Hinh. The currency used within the French Union was the French Indochinese piastre, notes were issued and managed by the Issue Institute of the States of Cambodia and Vietnam. First Indochina War French Indochinese piastre Vietnamese National Army French Indochina History of Vietnam
Parties engaging in the production or distribution of prohibited goods and services are members of the illegal economy. Examples include the trade, illegal currency transactions. Violations of the tax code involving income tax evasion constitutes membership in the unreported economy, because tax evasion or participation in a black market activity is illegal, participants will attempt to hide their behavior from the government or regulatory authority. Cash usage is the medium of exchange in illegal transactions since cash usage does not leave a footprint. Common motives for operating in markets are to trade contraband, avoid taxes and regulations. Typically the totality of such activity is referred to with the article as a complement to the official economies, by market for such goods and services. Black money is the proceeds of a transaction, on which income and other taxes have not been paid. Because of the nature of the black economy it is not possible to determine its size. There is no single underground economy, there are many and these underground economies are omnipresent, existing in market oriented as well as in centrally planned nations, be they developed or developing.
Different types of activities are distinguished according to the particular institutional rules that they violate. Illegal economy participants engage in the production and distribution of prohibited goods and services, such as trafficking, arms trafficking. The unreported economy consists of economic activities that circumvent or evade the institutionally established fiscal rules as codified in the tax code. A summary measure of the economy is the amount of income that should be reported to the tax authority but is not so reported. A complementary measure of the economy is the tax gap. In the U. S. unreported income is estimated to be $2 trillion resulting in a tax gap of $450–$500 billion, the unrecorded economy consists of those economic activities that circumvent the institutional rules that define the reporting requirements of government statistical agencies. A summary measure of the economy is the amount of unrecorded income. Unrecorded income is a problem in transition countries that switched from a socialist accounting system to UN standard national accounting.
New methods have been proposed for estimating the size of the unrecorded economy, but there is still little consensus concerning the size of the unreported economies of transition countries
Fall of Saigon
The event marked the end of the Vietnam War and the start of a transition period to the formal reunification of Vietnam under the Socialist Republic. This bombardment at the Tân Sơn Nhất Airport killed the last two American servicemen to die in Vietnam, Charles McMahon and Darwin Judge. By the afternoon of the day, North Vietnamese troops had occupied the important points of the city. The South Vietnamese government capitulated shortly afterward, the city was renamed Hồ Chí Minh City, after the Democratic Republics late President Hồ Chí Minh. The evacuation culminated in Operation Frequent Wind, the largest helicopter evacuation in history, in addition to the flight of refugees, the end of the war and institution of new rules by the communists contributed to a decline in the citys population. Various names have applied to these events. The Vietnamese government officially calls it Day of liberating the South for national reunification or Liberation Day and it is called the Ngày mất nước, Tháng Tư Đen, Ngày Quốc Nhục, or Ngày Quốc Hận by many Overseas Vietnamese who were refugees from communism.
The rapidity with which the South Vietnamese position collapsed in 1975 was surprising to most American and South Vietnamese observers, and probably to the North Vietnamese and their allies as well. For instance, a prepared by the CIA and U. S. Army Intelligence. These predictions proved to be grievously in error, even as that memo was being released, General Dũng was preparing a major offensive in the Central Highlands of Vietnam, which began on 10 March and led to the capture of Buôn Ma Thuột. The ARVN began a disorderly and costly retreat, hoping to redeploy its forces and hold the part of South Vietnam. Along the way, disorderly South Vietnamese retreats and the flight of refugees—there were more than 300,000 in Đà Nẵng—damaged South Vietnamese prospects for a turnaround. By April 8, the North Vietnamese Politburo, which in March had recommended caution to Dũng, cabled him to demand “unremitting vigor in the all the way to the heart of Saigon. ”On April 14, they renamed the campaign the Hồ Chí Minh campaign, after revolutionary leader Hồ Chí Minh.
Meanwhile, South Vietnam failed to any significant increase in military aid from the United States. On April 9, PAVN forces reached Xuân Lộc, the last line of defense before Saigon, the North Vietnamese front line was now just 26 miles from downtown Saigon. With the ARVN having few defenders, the fate of the city was effectively sealed, the ARVN III Corps commander, General Toan, had organized five centers of resistance to defend the city. These fronts were so connected as to form an arc enveloping the area west, north. South Vietnamese defensive forces around Saigon totaled approximately 60,000 troops, however, as the exodus made it into Saigon, along with them were many ARVN soldiers, which swelled the men under arm in the city to over 250,000
The Zimbabwean dollar was the official currency of Zimbabwe from 1980 to 12 April 2009. During this time, it was subject to periods of above average inflation, the Zimbabwe dollar was introduced in 1980 to directly replace the Rhodesian dollar at par, at a similar value to the US dollar. Over time, hyperinflation in Zimbabwe reduced the Zimbabwe dollar to one of the lowest valued currency units in the world and it was redenominated three times, with denominations up to a $100 trillion banknote issued. The final redenomination produced the fourth dollar, which was worth 1025 ZWD, use of the Zimbabwean dollar as an official currency was effectively abandoned on 12 April 2009. It was demonetised in 2015, with outstanding accounts able to be reimbursed until April 30,2016, the Zimbabwean dollars predecessor, the Rhodesian dollar, was essentially equal to half of the value of the Pound sterling at the time it was adopted. The same practice which was used in other Commonwealth countries such as South Africa and New Zealand.
The selection of the name was motivated by the fact that the value of the new unit correlated more closely to the value of the US dollar than it did to the pound sterling. The reverse side of dollar notes often illustrated the culture or landmarks of Zimbabwe, the first Zimbabwean dollar was introduced in 1980 and replaced the Rhodesian dollar at par. The initial ISO4217 code was ZWD, in October 2005, the head of the Reserve Bank of Zimbabwe, Dr. Gideon Gono, announced that Zimbabwe would have a new currency the following year, and new banknotes and coins would be produced. However, in June 2006, it was decreed that, for a new currency to be viable, instead, in August 2006, the first dollar was redenominated to the second dollar at the rate of 1000 first dollars to 1 second dollar. At the same time, the currency was devalued against the US dollar, from 101000 first dollars to 250 second dollars, a decrease of about 60%. ISO originally assigned a new code of ZWN to this redenominated currency.
The revaluation campaign, which Gideon Gono named Operation Sunrise, was completed on 21 August 2006 and it was estimated that some ten trillion old Zimbabwe dollars were not redeemed during this period. The following year, on 2 February 2007, the RBZ revealed that a new dollar would be released, with inflation at the time still in the four digits, the banknotes remained in storage. During the same month, the Reserve Bank of Zimbabwe declared inflation illegal, on 30 July 2008, the dollar was redenominated. After 1 August 2008, ZW$10 billion were worth ZW$1, the new currency code was ZWR. The denominations to be issued were coins valued Z$5, Z$10 and Z$25, and banknotes worth Z$5, Z$10, Z$20, Z$100, and Z$500. Due to frequent cash shortages and the apparently worthless Zimbabwean dollar and this program officially allowed a number of retailers to accept foreign money
Vietnam, officially the Socialist Republic of Vietnam, is the easternmost country on the Indochina Peninsula in Southeast Asia. With an estimated 92.7 million inhabitants as of 2016, it is the worlds 14th-most-populous country, and its capital city has been Hanoi since the reunification of North and South Vietnam in 1976, with Ho Chi Minh City as a historical city as well. The northern part of Vietnam was part of Imperial China for over a millennium, an independent Vietnamese state was formed in 939, following a Vietnamese victory in the Battle of Bạch Đằng River. Following a Japanese occupation in the 1940s, the Vietnamese fought French rule in the First Indochina War, Vietnam was divided politically into two rival states, North Vietnam, and South Vietnam. Conflict between the two sides intensified in what is known as the Vietnam War, the war ended with a North Vietnamese victory in 1975. Vietnam was unified under a communist government but remained impoverished, in 1986, the government initiated a series of economic and political reforms which began Vietnams path towards integration into the world economy.
By 2000, it had established relations with all nations. Since 2000, Vietnams economic growth rate has been among the highest in the world and its successful economic reforms resulted in its joining the World Trade Organization in 2007. It is a member of the Asia-Pacific Economic Cooperation and the Organisation Internationale de la Francophonie, Vietnam remains one of the worlds four remaining one-party socialist states officially espousing communism. The name Việt Nam is a variation of Nam Việt, a name that can be traced back to the Triệu Dynasty of the 2nd century BC. The word Việt originated as a form of Bách Việt. The form Vietnam is first recorded in the 16th-century oracular poem Sấm Trạng Trình, the name has been found on 12 steles carved in the 16th and 17th centuries, including one at Bao Lam Pagoda in Haiphong that dates to 1558. Then, as recorded, rewarded Yuenan/Vietnam as their nations name, to show that they are below the region of Baiyue/Bach Viet. Between 1804 and 1813, the name was used officially by Emperor Gia Long and it was revived in the early 20th century by Phan Bội Châus History of the Loss of Vietnam, and by the Vietnamese Nationalist Party.
The country was usually called Annam until 1945, when both the government in Huế and the Viet Minh government in Hanoi adopted Việt Nam. Archaeological excavations have revealed the existence of humans in what is now Vietnam as early as the Paleolithic age, Homo erectus fossils dating to around 500,000 BC have been found in caves in Lạng Sơn and Nghệ An provinces in northern Vietnam. The oldest Homo sapiens fossils from mainland Southeast Asia are of Middle Pleistocene provenance, teeth attributed to Homo sapiens from the Late Pleistocene have been found at Dong Can, and from the Early Holocene at Mai Da Dieu, Lang Gao and Lang Cuom. The Hồng Bàng dynasty of the Hùng kings is considered the first Vietnamese state, in 257 BC, the last Hùng king was defeated by Thục Phán, who consolidated the Lạc Việt and Âu Việt tribes to form the Âu Lạc, proclaiming himself An Dương Vương
Hydropower or water power is power derived from the energy of falling water or fast running water, which may be harnessed for useful purposes. A trompe, which compressed air from falling water, is sometimes used to power other machinery at a distance. In the late 19th century, hydropower became a source for generating electricity, cragside in Northumberland was the first house powered by hydroelectricity in 1878 and the first commercial hydroelectric power plant was built at Niagara Falls in 1879. In 1881, street lamps in the city of Niagara Falls were powered by hydropower, since the early 20th century, the term has been used almost exclusively in conjunction with the modern development of hydroelectric power. In China and the rest of the Far East, hydraulically operated pot wheel pumps raised water into crop or irrigation canals, the power of a wave of water released from a tank was used for extraction of metal ores in a method known as hushing. The method was first used at the Dolaucothi Gold Mines in Wales from 75 AD onwards, hushing was widely used in Britain in the Medieval and periods to extract lead and tin ores.
It evolved into hydraulic mining when used during the California Gold Rush and these include an endless belt with jugs attached, a cow-powered shadoof, and a reciprocating device with hinged valves. In 1753, French engineer Bernard Forest de Bélidor published Architecture Hydraulique which described vertical-, the growing demand for the Industrial Revolution would drive development as well. At the beginning of the Industrial Revolution in Britain, water was the source of power for new inventions such as Richard Arkwrights water frame. In the 1830s, at the peak in US canal-building, hydropower provided the energy to transport barge traffic up. Technological advances had moved the water wheel into an enclosed turbine or water motor. Francis, while working as engineer of Lowells Locks and Canals company. He applied scientific principles and testing methods to the problem of turbine design and his mathematical and graphical calculation methods allowed confident design of high efficiency turbines to exactly match a sites specific flow conditions.
The Francis reaction turbine is still in use today. Hydraulic power networks used pipes to carrying pressurized water and transmit power from the source to end users. The power source was normally a head of water, which could be assisted by a pump and these were extensive in Victorian cities in the United Kingdom. A hydraulic power network was developed in Geneva, Switzerland. The world-famous Jet dEau was originally designed as the relief valve for the network
A currency in the most specific use of the word refers to money in any form when in actual use or circulation as a medium of exchange, especially circulating banknotes and coins. A more general definition is that a currency is a system of money in common use, under this definition, US dollars, British pounds, Australian dollars, and European euros are examples of currency. These various currencies are recognized stores of value and are traded between nations in exchange markets, which determine the relative values of the different currencies. Currencies in this sense are defined by governments, and each type has limited boundaries of acceptance, other definitions of the term currency are discussed in their respective synonymous articles banknote and money. The latter definition, pertaining to the systems of nations, is the topic of this article. Currencies can be classified into two systems, fiat money and commodity money, depending on what guarantees the value. Some currencies are legal tender in certain jurisdictions, which means they cannot be refused as payment for debt.
Others are simply traded for their economic value, digital currency has arisen with the popularity of computers and the Internet. Currency evolved from two basic innovations, both of which had occurred by 2000 BC, originally money was a form of receipt, representing grain stored in temple granaries in Sumer in ancient Mesopotamia, Ancient Egypt. In this first stage of currency, metals were used as symbols to represent value stored in the form of commodities and this formed the basis of trade in the Fertile Crescent for over 1500 years. Trade could only reach as far as the credibility of that military and it is not known what was used as a currency for these exchanges, but it is thought that ox-hide shaped ingots of copper, produced in Cyprus, may have functioned as a currency. It is thought that the increase in piracy and raiding associated with the Bronze Age collapse, possibly produced by the Peoples of the Sea, brought the trading system of oxhide ingots to an end. In Africa, many forms of value store have been used, including beads, ivory, various forms of weapons, the manilla currency, the manilla rings of West Africa were one of the currencies used from the 15th century onwards to sell slaves.
African currency is still notable for its variety, and in many various forms of barter still apply. These factors led to the metal itself being the store of value, first silver, now we have copper coins and other non-precious metals as coins. Metals were mined and stamped into coins and this was to assure the individual taking the coin that he was getting a certain known weight of precious metal. Coins could be counterfeited, but they created a new unit of account. Most major economies using coinage had several tiers of coins, using a mix of copper, gold coins were used for large purchases, payment of the military and backing of state activities, they were more often used as measures of account than physical coins
State Bank of Vietnam
The State Bank of Vietnam is the central bank of Vietnam. It currently holds an about 65% stake of VietinBank - the countrys largest listed bank by capital, when Indochina was under French rule, the colonial government governed the Indochinese monetary system through Indochinese Bank, which acted as a commercial bank in French Indochina. After the August Revolution in 1945, the government of the Democratic Republic of Vietnam gradually attempted to exercise a monetary system independent from France, on 6 May 1951, president Hồ Chí Minh signed decree 15/SL on establishment of National Bank of Vietnam. On 21 January 1960, the governor of the signed an ordinance on behalf of the prime minister to rename the bank State Bank of Vietnam. After the fall of Saigon, the two Vietnams were united but not until July 1976 did the two administrations and institutions unite. In July 1976, the National Bank of Vietnam was merged into the State Bank of Vietnam, in the Doi moi liberalisation era, the banking system of Vietnam was reformed.
The former prime minister, Nguyễn Tấn Dũng, was a governor while he held the post of deputy prime minister. There has been criticism of the quality of the new polymer đồng banknotes. Controversy surrounded the purchase of the house by governor Le Duc Thuy when he bought a house belonging to the bank one tenth of the market value. However, the government stopped the deal when the media reported the purchase, the State Bank of Vietnam is a ministry-level body under the administration of the government, the bank governor is a member of the cabinet. The governor is nominated by the prime minister subject to the approval of the National Assembly, vice governors are appointed by the prime minister on the recommendation of the governor. Both governor and vice governors serve a 5-year term, the State Bank of Vietnam defines its principal roles as, Promote monetary stability and formulate monetary policies. Promote institutions’ stability and supervise financial institutions, provide banking facilities and recommend economic policies to the government.
Provide banking facilities for the financial institutions, supervise all commercial banks’ activities in Vietnam. Lend the state money to the commercial banks, issue government bonds, organise bond auctions. Be in charge of other roles in management and foreign exchange rates List of banks in Vietnam Economy of Vietnam Vietnamese đồng State Bank of Vietnam official website
East Germany, formally the German Democratic Republic, was an Eastern Bloc state during the Cold War period. The Soviet zone surrounded West Berlin, but did not include it, as a result, the German Democratic Republic was established in the Soviet Zone, while the Federal Republic was established in the three western zones. East Germany, which lies culturally in Central Germany, was a state of the Soviet Union. Soviet occupation authorities began transferring administrative responsibility to German communist leaders in 1948, Soviet forces, remained in the country throughout the Cold War. Until 1989, the GDR was governed by the Socialist Unity Party, though other parties participated in its alliance organisation. The economy was centrally planned, and increasingly state-owned, prices of basic goods and services were set by central government planners, rather than rising and falling through supply and demand. Although the GDR had to pay war reparations to the USSR. Nonetheless it did not match the growth of West Germany.
Emigration to the West was a significant problem—as many of the emigrants were well-educated young people, the government fortified its western borders and, in 1961, built the Berlin Wall. Many people attempting to flee were killed by guards or booby traps. In 1989, numerous social and political forces in the GDR and abroad led to the fall of the Berlin Wall, the following year open elections were held, and international negotiations led to the signing of the Final Settlement treaty on the status and borders of Germany. The GDR was dissolved and Germany was unified on 3 October 1990, the GDR bordered the Soviet sector of Allied-occupied Berlin known as East Berlin which was administered as the states de facto capital. It bordered the three sectors occupied by the United States, United Kingdom and France known collectively as West Berlin. The three sectors occupied by the Western nations were sealed off from the rest of the GDR by the Berlin Wall from its construction in 1961 until it was brought down in 1989, the official name was Deutsche Demokratische Republik, usually abbreviated to DDR.
West Germans, the media and statesmen purposely avoided the official name and its abbreviation, instead using terms like Ostzone, Sowjetische Besatzungszone. The centre of power in East Berlin was referred to as Pankow. Over time, the abbreviation DDR was used colloquially by West Germans. However, this use was not always consistent, for example, before World War II, Ostdeutschland was used to describe all the territories east of the Elbe, as reflected in the works of sociologist Max Weber and political theorist Carl Schmitt
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a golden tinge. Nickel belongs to the metals and is hard and ductile. Meteoric nickel is found in combination with iron, a reflection of the origin of elements as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earths inner core, use of nickel has been traced as far back as 3500 BCE. Nickel was first isolated and classified as an element in 1751 by Axel Fredrik Cronstedt. The elements name comes from a mischievous sprite of German miner mythology, Nickel, an economically important source of nickel is the iron ore limonite, which often contains 1–2% nickel. Nickels other important ore minerals include garnierite, and pentlandite, major production sites include the Sudbury region in Canada, New Caledonia in the Pacific, and Norilsk in Russia. Nickel is slowly oxidized by air at room temperature and is considered corrosion-resistant, historically, it has been used for plating iron and brass, coating chemistry equipment, and manufacturing certain alloys that retain a high silvery polish, such as German silver.
About 6% of world production is still used for corrosion-resistant pure-nickel plating. Nickel-plated objects sometimes provoke nickel allergy, Nickel has been widely used in coins, though its rising price has led to some replacement with cheaper metals in recent years. Nickel is one of four elements that are ferromagnetic around room temperature, alnico permanent magnets based partly on nickel are of intermediate strength between iron-based permanent magnets and rare-earth magnets. The metal is valuable in modern times chiefly in alloys, about 60% of world production is used in nickel-steels, other common alloys and some new superalloys comprise most of the remainder of world nickel use, with chemical uses for nickel compounds consuming less than 3% of production. As a compound, nickel has a number of chemical manufacturing uses. Nickel is a nutrient for some microorganisms and plants that have enzymes with nickel as an active site. Nickel is a metal with a slight golden tinge that takes a high polish.
It is one of four elements that are magnetic at or near room temperature. Its Curie temperature is 355 °C, meaning that bulk nickel is non-magnetic above this temperature, the unit cell of nickel is a face-centered cube with the lattice parameter of 0.352 nm, giving an atomic radius of 0.124 nm