Manganese is a chemical element with the symbol Mn and atomic number 25. It is not found as a free element in nature. Manganese is a transition metal with a multifaceted array of industrial alloy uses in stainless steels. Manganese is named for pyrolusite and other black minerals from the region of Magnesia in Greece, which gave its name to magnesium and the iron ore magnetite. By the mid-18th century, Swedish-German chemist Carl Wilhelm Scheele had used pyrolusite to produce chlorine. Scheele and others were aware that pyrolusite contained a new element, but they were unable to isolate it. Johan Gottlieb Gahn was the first to isolate an impure sample of manganese metal in 1774, which he did by reducing the dioxide with carbon. Manganese phosphating is used for corrosion prevention on steel. Ionized manganese is used industrially as pigments of various colors, which depend on the oxidation state of the ions; the permanganates of alkali and alkaline earth metals are powerful oxidizers. Manganese dioxide is used as the cathode material in alkaline batteries.
In biology, manganese ions function as cofactors for a large variety of enzymes with many functions. Manganese enzymes are essential in detoxification of superoxide free radicals in organisms that must deal with elemental oxygen. Manganese functions in the oxygen-evolving complex of photosynthetic plants. While the element is a required trace mineral for all known living organisms, it acts as a neurotoxin in larger amounts. Through inhalation, it can cause manganism, a condition in mammals leading to neurological damage, sometimes irreversible. Manganese is a silvery-gray metal, it is hard and brittle, difficult to fuse, but easy to oxidize. Manganese metal and its common ions are paramagnetic. Manganese tarnishes in air and oxidizes like iron in water containing dissolved oxygen. Occurring manganese is composed of one stable isotope, 55Mn. Several radioisotopes have been isolated and described, ranging in atomic weight from 44 u to 69 u; the most stable are 53Mn with a half-life of 3.7 million years, 54Mn with a half-life of 312.2 days, 52Mn with a half-life of 5.591 days.
All of the remaining radioactive isotopes have half-lives of less than three hours, the majority of less than one minute. The primary decay mode before the most abundant stable isotope, 55Mn, is electron capture and the primary mode after is beta decay. Manganese has three meta states. Manganese is part of the iron group of elements, which are thought to be synthesized in large stars shortly before the supernova explosion. 53Mn decays to 53Cr with a half-life of 3.7 million years. Because of its short half-life, 53Mn is rare, produced by cosmic rays impact on iron. Manganese isotopic contents are combined with chromium isotopic contents and have found application in isotope geology and radiometric dating. Mn–Cr isotopic ratios reinforce the evidence from 26Al and 107Pd for the early history of the solar system. Variations in 53Cr/52Cr and Mn/Cr ratios from several meteorites suggest an initial 53Mn/55Mn ratio, which indicates that Mn–Cr isotopic composition must result from in situ decay of 53Mn in differentiated planetary bodies.
Hence, 53Mn provides additional evidence for nucleosynthetic processes before coalescence of the solar system. The most common oxidation states of manganese are +2, +3, +4, +6, +7, though all oxidation states from −3 to +7 have been observed. Mn2+ competes with Mg2+ in biological systems. Manganese compounds where manganese is in oxidation state +7, which are restricted to the unstable oxide Mn2O7, compounds of the intensely purple permanganate anion MnO4−, a few oxyhalides, are powerful oxidizing agents. Compounds with oxidation states +5 and +6 are strong oxidizing agents and are vulnerable to disproportionation; the most stable oxidation state for manganese is +2, which has a pale pink color, many manganese compounds are known, such as manganese sulfate and manganese chloride. This oxidation state is seen in the mineral rhodochrosite. Manganese most exists with a high spin, S = 5/2 ground state because of the high pairing energy for manganese. However, there are a few examples of S = 1/2 manganese.
There are no spin-allowed d–d transitions in manganese, explaining why manganese compounds are pale to colorless. The +3 oxidation state is known in compounds like manganese acetate, but these are quite powerful oxidizing agents and prone to disproportionation in solution, forming manganese and manganese. Solid compounds of manganese are characterized by its strong purple-red color and a preference for distorted octahedral coordination resulting from the Jahn-Teller effect; the oxidation state +5 can be produced by dissolving manganese dioxide in molten sodium nitrite. Manganate salts can be produced by dissolving Mn compounds, such as manganese dioxide, in molten alkali while exposed to air. Permanganate compounds are purple, can give glass a violet color. Potassium permanganate, sodium permanganate, barium permanganate are all potent oxidizers. Potassium permanganate called Condy's crystals, is a used laboratory reagent because of its oxidizing properties. Solutions of potassium permanganate were among the first stains and fixatives to be used in the preparation of biological cells and tissues f
Arun Shourie is an Indian economist, journalist and politician. He has worked as an economist with the World Bank, a consultant to the Planning Commission of India, editor of the Indian Express and The Times of India and a Minister of Communications and Information Technology in the Vajpayee Ministry, he was awarded the Ramon Magsaysay Award in 1982 and the Padma Bhushan in 1990. Arun Shourie was born in British India, on 2 November 1941 in a Brahmin family, he studied at Modern School and did his bachelor's in Economics from St. Stephen's College, Delhi University, he obtained his doctorate in Economics from the Maxwell School of Citizenship and Public Affairs at Syracuse University in 1966. Shourie is married to Anita, they have a son, his sister is the journalist Nalini Singh. Arun Shourie speaks about his personal life and reviews his life events as case dairies "My writing is like the case diary of an advocate, aimed at winning a case" and his opinions on journalism. Shortly after receiving PhD in economics from Syracuse University Shourie joined World Bank as an economist in 1967 where he worked for more than 10 years.
Between 1972–74, he was a consultant to the Indian Planning Commission and it was around this time that he began writing articles as a journalist, criticising economic policy. In 1975, during The Emergency imposed by prime minister, Indira Gandhi, Shourie began writing for the Indian Express in opposition to what he saw as an attack on civil liberties; the newspaper, owned by Ramnath Goenka, was a focal point for the government's efforts at censorship. He became a fellow of the Indian Council of Social Science Research in 1976. In January 1979, Goenka appointed Shourie as executive editor of the newspaper, giving him a carte blanche to do with it as he saw fit, he developed a reputation as an intelligent, fearless writer and editor who campaigned for freedom of the press, exposed corruption and defended civil liberties such that, in the words of Martha Nussbaum, "his dedication to the truth has won admiration throughout the political spectrum". Shourie has been called a "veteran journalist".
Shourie was a winner of the Ramon Magsaysay Award in 1982, in the Journalism and Creative Communication Arts category as "a concerned citizen employing his pen as an effective adversary of corruption and injustice." In 2000, he was named as one of the International Press Institute's World Press Freedom Heroes. He has been named International Editor of the Year Award and was awarded The Freedom to Publish Award, he was nominated from the state of Uttar Pradesh as a BJP representative for two successive tenures in the Rajya Sabha, thus being a Member of Parliament for 1998–2004 and 2004–2010. He held the office of the Minister of Disinvestment and Information Technology in the government of India under Vajpayee's prime ministership; as Disinvestment Minister, he led the sale of VSNL, Hindustan Zinc among others. Shourie was among many who objected to The Muslim Women Act 1986, which the government headed by Rajiv Gandhi proposed to alleviate communal violence and retain Muslim votes. Claimed by the government to be a reinforcement of India's constitutional secularism, it was criticised by both Muslims and Hindus.
The liberals among them, says Ainslie Embree, saw it as "a capitulation to the forces of Islamic obscurantism, a return... to the thirteenth century". Shourie wrote articles that tried to show that the treatment of women as required by the Quran would in fact offer them protection, although the application of Islamic law in practice was oppressing them, he was in turn criticised for what was perceived as a thinly-veiled attack on Islam itself, with Rafiq Zakaria, the Muslim scholar, saying that Shourie's concern for reform of Islam was in fact demonstrative of Hindu contempt that used the plight of Muslim women as an example of the backwardness of the community. Vir Sanghvi termed it "Hindu chauvinism with a liberal face". After the defeat of the BJP in 2009 general elections, Shourie asked for introspection and accountability within the party, he deplored factionalism within those who brief journalists to aid their own agenda. Shourie has been described by Christophe Jaffrelot, a political scientist, as "a writer sympathetic to militant Hindu themes" and has publicly voiced support for the aims of the Rashtriya Swayamsevak Sangh, a nationalist Hindutva organisation.
This has caused unease among some of those. He has said that, although he sees a danger from perceived Muslim violence such as the Godhra train burning incident of 2002, people have tended to redefine the "Hindutva" term, he says that prominent members of the Bharatiya Janata Party, of which he is a member and which has ties to the RSS — L. K. Advani and Atal Bihari Vajpayee — have shown their opposition to sectarian hatred and in their attempts to make the BJP inclusive have tried to marginalise those on both the Muslim and Hindu extremes who promote such hatred; as a political scientist he views that current leaders lack integrity. He emphasised his views in a cultural conference called Tomorrow’s India Global Summit and added that the pressure to bring about change in the present electoral system should come from the society. Arun Shourie has written numerous books. According to Martha Nussbaum, the traits of his writings are: recognisably the creation of a smart, muckraking journalist, They are polemical, ad hominem extremely shrill in tone....
But despite their style, the books are the work of a brilliant man, with a wide if idiosyncratic
In the field of waste management, extended producer responsibility is a strategy to add all of the environmental costs associated with a product throughout the product life cycle to the market price of that product. Extended producer responsibility legislation is a driving force behind the adoption of remanufacturing initiatives because it "focuses on the end-of-use treatment of consumer products and has the primary aim to increase the amount and degree of product recovery and to minimize the environmental impact of waste materials"; the concept was first formally introduced in Sweden by Thomas Lindhqvist in a 1990 report to the Swedish Ministry of the Environment. In subsequent reports prepared for the Ministry, the following definition emerged: " is an environmental protection strategy to reach an environmental objective of a decreased total environmental impact of a product, by making the manufacturer of the product responsible for the entire life-cycle of the product and for the take-back and final disposal.
EPR uses financial incentives to encourage manufacturers to design environmentally friendly products by holding producers responsible for the costs of managing their products at end of life. This policy approach differs from product stewardship, which shares responsibility across the chain of custody of a product, in that it attempts to relieve local governments of the costs of managing certain priority products by requiring manufacturers to internalize the cost of recycling within the product price. EPR is based on the principle that manufacturers have the greatest control over product design and marketing and have the greatest ability and responsibility to reduce toxicity and waste. EPR may take buyback, or recycling program; the producer may choose to delegate this responsibility to a third party, a so-called producer responsibility organization, paid by the producer for used-product management. In this way, EPR shifts the responsibility for waste management from government to private industry, obliging producers, importers and/or sellers to internalise waste management costs in their product prices and ensure the safe handling of their products.
A good example of a producer responsibility organization is PRO Europe S. P. R. L. Founded in 1995, the umbrella organization for European packaging and packaging waste recovery and recycling schemes. Product stewardship organizations like PRO Europe are intended to relieve industrial companies and commercial enterprises of their individual obligation to take back used products through the operation of an organization which fulfills these obligations on a nationwide basis on behalf of their member companies; the aim is to ensure the recovery and recycling of packaging waste in the most economically efficient and ecologically sound manner. In many countries, this is done through the Green Dot trademark of which PRO Europe is the general licensor. In twenty-five nations, companies are now using the Green Dot as the financing symbol for the organization of recovery and recycling of sales packaging. In response to the growing problem of excessive waste, several countries adopted waste management policies in which manufacturers are responsible for taking back their products from end users at the end of the products' useful life, or financing a collection and recycling infrastructure.
These policies were adopted due to the lack of collection infrastructure for certain products that contain hazardous materials, or due to the high costs to local governments of providing such collection services. The primary goals of these take-back laws therefore are to partner with the private sector to ensure that all waste is managed in a way that protects public health and the environment; the goals of take-back laws are to encourage companies to design products for reuse and materials reduction. Take-back programs help promote these goals by creating incentives for companies to design products that minimize waste management costs, to design products that contain safer materials, or to design products that are easier to recycle and reuse; the earliest take-back activity began in Europe, where government-sponsored take-back initiatives arose from concerns about scarce landfill space and hazardous substances in component parts. The European Union adopted a directive on Electronic Equipment.
The purpose of this directive is to prevent the production of waste electronics and to encourage reuse and recycling of such waste. The directive requires the Member States to encourage design and production methods that take into account the future dismantling and recovery of their products; these take-back programs have been adopted in nearly every OECD country. In the United States, most of these policies have been implemented at the state level. Recycling and taxation fails to adequately reduce the pollution caused by plastic bags. An alternative to these policies would be to increase extended producer responsibility. In the US, under the Clinton presidency, the President's Council on Sustainable Development suggested EPR in order to target different participants in the cycle of a product's life; this can, make the product more expensive since the cost must be taken into consideration before being put on the market, why it is not used in the United States currently. Instead, there is banning or taxation of plastic bags, which puts the responsibility on the consumers.
In the United States, EPR has n