April

#AtoZChallenge2015: Zn, for Zinc

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Today is the last post of this 2015 AtoZAprilChallenge, and it’s about this marvellous element Zinc, symbol Zn, and number 30 on the elements periodic table. Zinc has many fantastic properties, and is a major component of living things.

1943 Zinc Penny“Zinc, in commerce also spelter, is a chemical element with symbol Zn and atomic number 30. It is the first element of group 12 of the periodic table. In some respects zinc is chemically similar to magnesium: its ion is of similar size and its only common oxidation state is +2. Zinc is the 24th most abundant element in Earth’s crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest mineable amounts are found in Australia, Asia, and the United States. Zinc production includes froth flotation of the ore, roasting, and final extractionusing electricity (electrowinning).

Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea[2] and by the 7th century BC in Ancient Greece.[3] Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC.[4] To date, the oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc.[5] Alchemistsburned zinc in air to form what they called “philosopher’s wool” or “white snow”.

The element was probably named by the alchemist Paracelsus after the German word Zinke. German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Voltauncovered the electrochemical properties of zinc by 1800. Corrosion-resistant zinc plating of iron (hot-dip galvanizing) is the major application for zinc. Other applications are in batteries, small non-structural castings, and alloys, such as brass. A variety of zinc compounds are commonly used, such as zinc carbonate and zinc gluconate (as dietary supplements), zinc chloride (in deodorants), zinc pyrithione (anti-dandruff shampoos), zinc sulfide (in luminescent paints), and zinc methyl or zinc diethyl in the organic laboratory.

Zinc is an essential mineral perceived by the public today as being of “exceptional biologic and public health importance”, especially increasingly regarding prenatal and postnatal development.[6] Zinc deficiency affects about two billion people in the developing world and is associated with many diseases.[7] In children it causes growth retardation, delayed sexual maturation, infection susceptibility, and diarrhea.[6] Enzymes with a zinc atom in the reactive center are widespread in biochemistry, such as alcohol dehydrogenase in humans.[8] Consumption of excess zinc can cause ataxia, lethargy and copper deficiency…

Various isolated examples of the use of impure zinc in ancient times have been discovered. Zinc ores were used to make the zinc–copper alloy brass many centuries prior to the discovery of zinc as a separate element. Judean brass from the 14th to 10th centuries BC contains 23% zinc.[2]

Knowledge of how to produce brass spread to Ancient Greece by the 7th century BC, but few varieties were made.[3] Ornaments made of alloys containing 80–90% zinc, with lead, iron, antimony, and other metals making up the remainder, have been found that are 2,500 years old.[17] A possibly prehistoric statuette containing 87.5% zinc was found in a Dacian archaeological site.[49]

The oldest known pills were made of the zinc carbonates hydrozincite and smithsonite. The pills were used for sore eyes and were found aboard the Roman ship Relitto del Pozzino, which wrecked in 140 BC.[50][51]

The manufacture of brass was known to the Romans by about 30 BC.[52] They made brass by heating powdered calamine (zinc silicate or carbonate), charcoal and copper together in a crucible.[52] The resulting calamine brass was then either cast or hammered into shape for use in weaponry.[53] Some coins struck by Romans in the Christian era are made of what is probably calamine brass.[54]

Strabo writing in the 1st century BC (but quoting a now lost work of the 4th century BC historian Theopompus) mentions “drops of false silver” which when mixed with copper make brass. This may refer to small quantities of zinc that is a by-product of smelting sulfide ores.[55] Zinc in such remnants in smelting ovens was usually discarded as it was thought to be worthless.[56]

The Berne zinc tablet is a votive plaque dating to Roman Gaul made of an alloy that is mostly zinc.[57]

The Charaka Samhita, thought to have been written between 300 and 500 AD,[58] mentions a metal which, when oxidized, produces pushpanjan, thought to be zinc oxide.[59]Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period. The smelting of metallic zinc here, however, appears to have begun around the 12th century AD.[60][61] One estimate is that this location produced an estimated million tonnes of metallic zinc and zinc oxide from the 12th to 16th centuries.[19] Another estimate gives a total production of 60,000 tonnes of metallic zinc over this period.[60] The Rasaratna Samuccaya, written in approximately the 13th century AD, mentions two types of zinc-containing ores: one used for metal extraction and another used for medicinal purposes.”

About Zinc and health: http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/

Zinc in food: http://www.whfoods.com/genpage.php?tname=nutrient&dbid=115

Image: http://www.publicdomainpictures.net/view-image.php?image=10228&picture=1943-zinc-penny&large=1

#AtoZChallenge2015: Family

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Marc Chagall Paris LandscapeOne of the pleasures of the A to Z is, for me, to dive again in Raymond Williams’ Keywords, a source of inspiration and learning. The simplest words reveal their history, the meanings given to them in the past, by people like us, our older neighbours, perhaps our ancestors. On Family Williams wrote:

“Family has an especially significant social history. It came into English in the 14-15th century, from Latin familia – household – and famulus – servant. The associated adjective familiar appears to be somewhat earlier in common use, and its range of meanings reminds us of the range of meanings which were predominant in family before the 17th century. There is the direct sense of the Latin household, either in the sense of a group of servants or a group of blood-relations and servants living together in one house. Familiar related to this, in phrases like familiar angel, familiar devil and the later noun familiar, where the sense is of being associated with or serving someone. There is also the common 15 and 16th century phrase familiar enemy, to indicate an enemy within one’s household, ‘within the gates’, and thence by extension an enemy within one’s own people. But the strongest early senses of familiar were those which are still current in modern English: on terms of friendship or intimate with someone (cf. ‘don’t be too familiar’); well known, well used to or habitual (cf. ‘familiar in his mouth as household words’, Henry V). These uses came from the experience of  people living together in a household, in close relations with each other and well used to each other’s way. They do not, and familiar still does not, relate to the sense of blood-group.

Family was then extended, from at least the 15th century, to describe not a household but what was significantly called a house, in the sense of a particular lineage or kin-group, ordinarily by descent from a common ancestor. This sense was extended to indicate a people or group of peoples, again with a sense of specific descent from an ancestor; also to a particular religious sense, itself associated with previous social meanings, as in ‘the Father of our Lord Jesus Christ, of whom the whole family in heaven and earth is named’ (Ephesians, 3:14, 15). Family in the Authorised Version of the Bible (1611) was restricted to these wide senses: either a large kin-group, often virtually equivalent to tribe (Genesis 10:5; 12:3; Jeremiah 1:15; 31:1; Ezekiel 20:32) or the kin-group of a common father: ‘and then shall he (a brother) depart from thee, both he and his children with him, and shall return unto his own family, and unto the possession of his fathers shall he return’ (Leviticus 25:41). The 16 and 17th century sect of the Family of Love or Familists is interesting in that it drew the sense of a large group, but made this open and voluntary through love.

In none of the pre-17th century senses, therefore, can we find the distinctive modern sense of a small group confined to immediate blood relations…”

Image: Marc Chagall Paris Landscape, 1978

#FiveSentenceFiction: Hunt #Easter

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DSC_0012Sunshine filters through the young leaves, bright eyes looking for bright colours.

In the grass, at the foot of small bushes, there they are, half hidden.

The Bunny has done a good job: not to hard to find, but still needs a little effort, and plenty they are…

Mother has given the children small bowls, for them to collect the eggs,

Their little feet trample the green carpet, soon it will be tea time.

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and sometimes
when the moon sucks the wood…

Redwater Ramblings

Turn back time and I will be
as of the wind
sugarcrafted on the skin
with pause for eyes the nose
salacious teethings
and sometimes
when the moon sucks the wood
from yonder trees
and chiff-chaffs stick
their nosey points towards
grey bony threads of
sickle-clouds
remember me
when all is sifted and I a
graft
a slump and spendage
around the shoulders
of stalwart better things

© Eve Redwater 2012

[Posted for Dverse – Meeting the Bar: Allegory – come join the allegorical fun! Also, remember you can always click on my photographs for a bigger view~]

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A two-day break…

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A Moveable FeastThought it was time for a break. March was a busy month, plenty to read and more writing. And a wedding! We enjoyed the long walks, and in recent weeks the beautiful weather. We’ll find some light rain in Paris on Wednesday. Then we’ll be visiting my childhood place (Happy days in Clichy…) Have a couple of posts up my sleeve for the #AtoZChallenge for April… Will travel, will take pics…

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