Redox Art





 Andy Warhol, Oxidation Painting, 1978
Metallic pigment in acrylic medium and urine on canvas



Andy Warhol (August 6, 1928 – February 22, 1987) was an American artist who was a leading figure in the visual art movement known as pop art.

In the late 1970s and early 1980s, Andy Warhol focused for the first time on the exploration of abstraction. … … In December 1977 Warhol began the Oxidations, iridescent canvases made up of coppery yellows, oranges, and greens. Surprisingly, the only paint used by the artist in this very “painterly” work was the metallic copper background. Warhol invited friends and acquaintances to urinate onto a canvas covered in metallic paint in order to cause oxidation. The uric acid reacted with the copper in the paint removing components of the pure metal to form mineral salts. Some colours developed immediately while others like blue and green formed later on top of the red or brown copper oxides. Warhol and his collaborators experimented with both pattern and coloration by using a variety of metallic background paints and by varying the maker’s fluid and food intake.

More science behind the art:

Transition metals (such as copper) will form coloured compounds. The colour of the compound depends on the metal’s oxidation state and the type of accompanying ion present.

Substance	Colour	Substance	Colour
Copper(I) oxide	Red	Chromium (III) oxide	Green
Copper (II) oxide	Black	Potassium chromate (K2CrO4)	Yellow
Copper (II) sulfate	Blue	Potassium dichromate (K2Cr2O7)	Orange
Copper (II) carbonate	Green

Andy Warhol, Oxidation Painting 1978



GREEN W~A~V~E!!!

The Green Wave is a global biodiversity campaign about biodiversity. Each year, local schools and various different countries will be planting their own local tree species on the same day and same time (TUESDAY 22 May, 1000am). To know more about the GREEN WAVE, visit http://greenwave.cbd.int/en/home

Our school had participated in this event by planting a local tree called Syzygium polyanthum behind Mr Low's office.

Here are some details of Syzygium polyanthum:

Habit 

Medium to tall tree, growing up to 20-30 metres in height. Crown is open, oval or cylindrical in shape.

Leaves

Small to medium-sized, simple, elliptical and narrowing towards both ends. Light green in colour, and when crushed, gives off a smell of “Jambu”. New emerging leaves are reddish in colour.

Flowers

Creamy white in colour, turning pale-pink, slightly fragrant and occur in small clusters on the bare twigs.

Fruits/Seeds

Small round and pulpy, 1 centimetres wide or less, often flattened and ripening red to purple-black.

Interesting Facts

The young leaves, which have a slightly sour taste, are a commonly used spice in Southeast Asian cuisine that is particularly popular in Indonesia. Fresh or dried leaves are added to meat, vegetable and rice dishes, such as curries and stews.

In Malaysia, a poultice prepared from leaves, roots and bark is applied to the skin to provide anti-itch relief. In Indonesia, leaf infusions and bark extracts are used to treat diarrhoea.

Being a moderately hard to hard wood, it is used to make furniture, as well as building material for home construction. In the Dutch Indies, a bark infusion was once used to tan fishing nets and dye bamboo mats. The tree is sometimes planted in the understory of tree plantations to inhibit growth of weeds. The leaves are good mulching material, because they decompose slowly.

Here are some photos taken on 22 March:

Digging the hole

Planting the tree



Mrs Tan planting the tree

The "GREEN" People



One of the great functions trees offers, besides its aesthetic addition, is the sequestering of CO₂, carbon dioxide. This directly reduces the growth of the Greenhouse Effect and counteracts Global Warming. Studies show that a single tree can soak up as much as 48 pounds of carbon dioxide in a year and produce enough oxygen to sustain two human beings.

Thus, what we can actually do to help the Earth is to plant a tree.  It seems like such a simple and menial task.  But the truth is; every tree makes a difference.

While many of you are busy and are not able to make it physically to witness the Green Wave, you can still do your part for "tree planting" too. Northwest CDC is embarking on a charity drive where New York Skin Quest will donate $15 for every correct quiz answered (total 15 MCQ). Don't just say "I will do my best to save the earth"! Action speaks louder than words! So, log on to http://www.ecoquestatnorthwest.sg/index.php to complete the quiz! It only takes 10 min of your time.  



Do your part!

Do your part for the community by being an Eco-Hero!

EcoQuest @ North West is a programme where residents and students learn about Green Living. You can be part of it by participating in the five green pillars quizzes. Each participant who scores a quiz corretly will see $3 donated to the North West Food Aid Fund. 5 quizzes will mean that $15 is donated!

The quiz can be accessed at this website: http://ecoquestatnorthwest.sg/. All information to score full marks for the quiz can be found on the same website! This quiz ends 30 April 2012.

Do your part!

World Water Day 2012

March was about environmental (water) advocacy.

World Water Day was commemorated on 22 March all around the world. Awareness about water shortages and constraints were heightened and we could learn about and emphatise with nations that faced serious water shortages.
Singapore has a water challenge and we try to overcome this challenge using technology (NEWater!). Currently, there are 4 NEWater plants in Singapore. The latest and the largest NEWater plant at Changi with a capacity of 50mgd was opened in May 2010. With this addition, coupled with the expansion of the existing plants, NEWater now meets 30% of Singapore’s total water demand. By 2060, NEWater is projected to meet 50% of Singapore’s future water demand.

Learn more about NEWater here: http://www.pub.gov.sg/about/historyfuture/Pages/NEWater.aspx

Find out more about how World Water Day is celebrated all over the world here: http://www.unwater.org/worldwaterday/

Important Message Signal On Total Defence Day

Total Defence Day is marked annually on February 15 in Singapore to commemorate the anniversary of the surrender of the British to the Japanese on February 15, 1942. It serves as a reminder that Singapore is defensible and is worth defending, and only Singaporeans would have the will to defend Singapore.

At 12:05 pm, the Singapore Civil Defence Force (SCDF) will sound the 1 minute long Important Message Signal through the island-wide Public Warning System (PWS) sirens. The 10 local radio station will then explain the appropriate measures to be taken for the three different types of PWS signals.

Besides the ‘Important Message’ signal (characterised by pulsating blasts), the two other signals are the ‘Alarm’ and the ‘All Clear’ signals, which are characterised by wailing and continuous blasts respectively. The sounding is part of SCDF’s continuous efforts to familiarise the public with the three PWS signals and raise awareness on how they should react upon hearing each signal.

From this exercise, we can see that sound is all around us and it plays a central part in our daily life. Besides using sound to communicate important information, sound also provides us with music which can have a powerful emotional effect on people. So have you wondered how is sound produced? Why are there so many different type of sound?

Sound is produced when an object moves or vibrates causing the particles around it to vibrate creating a series of compression and rarefaction. Our ears vibrate in a similar way to the original source of the vibration, allowing us to hear many different sounds.

Music can be generated when we vary the frequency, amplitude and harmonic constitution, or waveform of the sound wave which will in turn affect the pitch, loudness(or intensity) and quality(or timbre) of the sound respectively.

Here are some interesting sound experiments that you can try at home.

Old but Shiny??

In the olden Chinese New Year Tradition, red envelopes are given to children containing brand new money.
Now you can make old copper coins shiny and new with this science activity!

Instructions:

1. Ask your parents for a few Singapore 1 cent coins. (pennies from the United States of America works too!)
2. Combine 1/2 cup vinegar with 4 tablespoons salt. Stir until the salt dissolves.
3. Drop copper coins into mixture, wipe off with towel, rinse in water and dry. This will make them shine!

Alternatively, you may dip a toothbrush into the mixture to scrub the pennies, rinse in water and dry. This will make them shine too!

Science Bites:

Copper coins or pennies get dull over time because the copper slowly reacts with oxygen in the air to form copper oxide. Pure copper metal is bright and shiny, but the oxide is dull and greenish. When you place the copper coins or pennies in the salt and vinegar solution, the acetic acid from the vinegar dissolves the copper oxide, leaving behind shiny clean pennies. The copper from the copper oxide stays in the mixture of salt and vinegar. You could use other acids instead of vinegar, like lemon juice too!

National Day – Floating Platform @ Marina Bay

In the past, the National Day Parade was always held in the National Stadium. Besides being the venue for the National Day Parade 18 times, the stadium that could hold a capacity of 55, 000 people has also played host to many sporting, cultural, entertainment and national events, such as the Southeast Asian Games, Singapore Armed Forces Day, Singapore Youth Festival Opening Ceremony and the finals of the 2004 Tiger Cup.

However, the National Stadium was officially closed on 30 June 2007 and is scheduled to be demolished to make way for the Singapore Sports Hub which is expected to open in 2014. Hence, the Float @ Marina Bay was built as a temporary stadium for the next 5 years in lieu of the closure of the National Stadium.

The Float @ Marina Bay also known as the Marina Bay Floating Platform is the world’s largest floating stage. It is located on the waters of the Marina Reservior. Made entirely of steel, the floating platform on Marina Bay measures 120 m by 83 m and can bear up to 1,070 tonnes, equivalent to the total weight of 9,000 people, 200 tonnes of stage props and three 30-tonne military vehicles. The gallery at the stadium has a seating capacity of 30,000 people.

The density of an object is defined as its mass per unit volume.

Mass: amount of matter contained in an object and is commonly measured in kilograms (kg).

Volume: amount of space taken up by the matter and is commonly expressed in cubic meters (m³).

Units used to express density : kilogram per cubic meter (kg/m³) or grams per cubic centimeter (g/cm³).

Note: 1 g/cm³ = 1000 kg/m³

Different objects have different density.

 

                                        Densities of common substances

The ability of an object to "float" when it is placed in a fluid is called buoyant force, and is related to density. If an object is less dense than the fluid in which it is placed, it will float. If it is denser than the fluid, it will sink.

A steel ship will float even though it may be made of steel (which is much denser than water), because it encloses a volume of air (which is much less dense than water), and the resulting shape results in a total density that is less than that of the water. The same principle applies to the floating platform. Although it is made of steel, it has a large surface area and encloses a volume of air which makes it less dense than water. Thus, the platform could support a weight of 1, 070 tonnes without sinking.