It snows in the weekends in Minneapolis

Call it conspiracy, call it weather engineering, it is no secret, Minneapolis weekends are reserved for rain or snow.

Anyway, enjoy the beauty of snow, it looks nice when viewed in picture or warm comfort of the glass wall.

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The place where I stay is a very quite. Minneapolis is not a particularly famous tourist destination. But every place has it’s own special beauty.

Fall color is a special thing in Minneapolis. Rivers, lakes and colorful trees make a perfect setting for winter.
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Splitting water

Splitting water is easiest thing in the earth. All you need is a source of direct current a.k.a battery eliminator, some long wire, a plastic dish (deep) to keep water and couple of test tubes to collect what comes out of the split.

Tie the test tubes as shown with a cloth clip using a rubber band. Fill the tubes with water, add some salt to reduce the resistance. Shove open end of the cable inside test tube.

It may be a good idea to attach a gas carbon rod taken out from battery. This will protect the wire from erosion.
Once you do this, as I have done – you will notice bubbles coming out from end of the wire. These are Hydrogen and Oxygen.

What we did – is known as electrolysis a big word that means splitting by electricity.

Try electrolysis with concentrated salt water, let me know what did you notice.

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Making the first element — Hydrogen

Hydrogen – it is perhaps the simplest of the atoms and most abundant in universe. Consisting of just a proton and an electron it occupies the very first box of periodic table. Abundance of Hydrogen in universe is perhaps a good proof that our universe is young, with lot of energy to spend before it starts collapsing under its own weight.

To make hydrogen in your home you will need a pile of nails, about 50 gms
will do nicely. You will also need Hydrochloric Acid. Muriatic Acid sold to clean toilets etc. is a good source of HCl for our purpose.
For the experiment we shall use a glass bottle, with a two hole stopper. Put a glass tube that should go near the bottom and project out by at least 70mm out side. In the other hole insert a short tube. With the short tube attach a rubber tube about 50cm in length. Fill 1/5th of the bottle with nails. Then pour water till 1/3 of bottle. Then pour Muriatic acid to cover 2/3rd of the bottle. Quickly place the stopper on the bottle, taking care not to break the glass tube. Place the bottle on a tray. You will notice hydrogen bubbles coming out from the nails. Now take other end of the rubber pipe under a shallow through, and collect the gas in a water-filled test tube. Gas bubble will replace the water to fill the test tube.

You will notice Hydrogen is a colorless gas. If you take a lighted stick the gas will explode with a “pop” sound. Hydrogen explodes in presence of oxygen. As time goes the gas will have little oxygen mixed with it, then it will burn slowly with a bluish flame. If manage to blow a bubble with the gas, this will fly, as Hydrogen is lighter than air. Actually it the lightest of all elements.

Think of other things that you can do with hydrogen and write to me how your experiment go.

Good Luck!

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“A place for every thing

and every thing in it’s place.

That’s the way to sure success.”

There is nothing more convenient and peaceful than having a place on your own where you can do all your experiments without disturbance. For our work it does not take much to achieve that.


I use a simple rack for my work now. It has all my chemicals, labware and place for doing the work. On top, I keep the work. It has a test tube stand. A small plastic container to dispose chemicals, another small bottle to keep little distilled water to give final rinse to the lab ware. Rest keep changing on the need. I have a small pad of insulating material to keep hot bottles, glassware. Two spirit lamps for heating and glass works. I do take a little liberty of using few labware – it is there with me for last thiry years – two 100 ml beaker and two 250ml flask, besides couple of test tubes. These come handy as you can easily heat them and watch what’s going on inside. But these are not at all essential. Normal bottles would do just right.


If you have luxury of a big place available for your work, then you may spend a few buck on a Lab table. I had one such during my student days. Very convenient but takes lot of space.

Modern cramped flats where space is in big premium, you can probably get a wall unit made. The sketch given below will serve most requirement. You can extend the rack on top or bottom to store more items and chemicals. Drop down lid folds away to release space when it is not required. At the same time it is ideal to save unfinished work. If you have toddlers around in the house, it is essential that you keep all your chemical under lock and key.

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Chemistry of electricuty – let’s explore battery

Enough of talking about resource. Let’s get started with our first experiment. We shall see how a battery work and also salvage some raw material for our next experiment.
For this you need two exhausted zinc battery. Do not try this with alkaline cells or rechargeable ones – they contain some pretty corrosive chemical that we are not yet equipped to handle. You will require atleast two batteries to get material for our next experiments. That should not be a difficult task I suppose. Big UM3 size batteries are good, but AAA cells will also do.
If you have paper covered battery then your work is simple. But most batteries now have a metal leakproof jacket – it makes the task a bit difficult. Carefully with help of a plier remove the outer jacket. Inside you will find a grey colored tube – which should be heavily perforated by now by the corrosive chemical reaction that takes place inside the battery.
Carefully open the zinc casing from top. Inside you will find a dirty mixture of black powder and some paste. THese are manganese dioxide and ammonium chloride mixture. There will be some glue, and graphite powder. At the center there is a black rod – made of gas carbon. We need these rods in intact condition – take care not to break them.
Carefully disassemble the different parts on a old newspaper.scrape resedue out of zinc casing. Now pour the black mixture of MnO2 & NH4CL in a wide mouthed bottle. Pour about 70ml of water and mix it well to dissolve all soluble chemicals. If required pour a bit more. Decant and
then filter using funnel and filter paper. Old news paper makes excellent filter paper. The black resedue is primarily manganese di-oxide and solution has primarily ammonium chloride. Dry the solution in a shallow dish. You will get white powder of ammonium chloride. Some Zinc chloride and other impurities will also be present. Wash the zinc casing in tapwater.
Once you are done, save the four parts – Zinc, Manganese di-oxide, gas carbon rod and ammonium chloride in separate container. We shall use them in our later experiments.
Wash the zinc casing keep it aside in a wide mouth bottle.

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Setting up a home chemistry lab

Chemistry or for that matter all science experimentation has become obsolete as hobby. I used to have a small chemistry laboratory when I was kid and spend countless hours in doing my small experiments. This has helped me immensely in understanding science and many other related subjects in most enjoyable way. Now I am father of two kids and wanted to help my kids setup some lab of their own. To my utter surprise, I found science kits are taboo subject. Trying to buy chemical reagents look down upon. If you ask around you are viewed as potential terrorist or a drug baron.
As a kid 30 years ago, I had no difficulty in getting small quantity of nitric acid. My friendly neighborhood store owner did enquire me about the purpose and cautioned me about the hazard. But once he was satisfied that I do intend to use these for my experiment he encouraged me and actively helped me to source many other things that I did not know where to get. But
things have changed. Now, most of those chemicals are not available easily. Even where these are available, there you can only get them in bulk quantity on 1 litre odd pack. For home experiments I need hardly 50ml of these. I understand, keeping even these at home has become a law and order issue in some part of the world. With all these, I thought of writing this blog on doing simple chemistry experiments at home.
You don’t need to spend much for doing most chemistry experiments. Only thing you require is to know the chemicals available around you and innovate to use them. In fact you can start a chemistry laboratory with an investment of as little as Rs. 50/-. This is my aim, to help all to learn chemistry by the fun way.
To setup your own small chemistry first think of the space that you can get. You won’t need a very big space. A corner of a balcony, a space below staircase is more than sufficient for your purpose. You need a place to keep your things handy. A small rack is excellent for the purpose. A small table will be a luxury. If you are constrained for space, consider a 4inch deep wall mounted rack. At bottom of the rack you can fit a drop down lid that will serve as your work table. Whatever you get, plan where will keep your things and keep things in orderly manner.
“Keep a place for every thing
and keep everything in its place.
That is the road of sure success.”
I give my suggested layout for all the three category of setup. This is by no means the ultimate. Use whatever available to you easily and improvise to suit your requirement. To do the experiment that I will describe in this blog later, you will need three wide mouthed jar. Discarded jam or mayonnaise jars will be perfect. You will also need three glass bottle.
100ml medicine bottles will do. You need to keep rather large supply of distilled water. You can buy it from petrol pump or take it from refrigerator or air conditioner. The discharge water during defrosting or from AC outlet is good enough purity level for our experiment. Keep this in
a discarded cold drink bottle. You will also need a supply of glass bottles to keep your chemicals. I prefer, glass bottle with plastic caps for these. I do not have much patient to accumulate them over time and prefer to buy them from junk shop. This way, I can easily get bottles in uniform size and shape easily. You will require about twenty bottle for the chemicals. You will also need a funnel, a plastic one will, a glass one is excellent. If you can get a pack of filter paper. Even newspaper can be used as filter paper but the result may not be consistent.
You will need about 2m of glass tube of 5mm dia. and 1m of rubber tube. Six test tube and about ten rubber stopper will get you started with your own chemistry lab. Rubber stoppers requires some planning. Below, I give bare minimum requirement:

Stopper for test tube

  • Without any hole – 3 Nos
  • With 1 hole – 1
  • With 2 hole – 2

Stopper for 100ml bottle

  • with 2 hole – 3
  • With 1 hole – 3
  • without hole – 2

The hole should allow 5mm glass tube to be fitted snugly. You should try to get the stoppers with pre-drilled holes or get someone to make the holes for you. If you fail to do either then may be you should consider buying a cork borer.
You will also need a pliers and a battery eliminator for some of the experiments. With these, you are ready to venture into the land of chemicals.

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Kidneys of Kolkata


Kidneys of Kolkata

Posted On Saturday, May 30, 2009 at 12:11:16 PM

The East Kolkata wetlands fed by sewage water is a picture-pretty place
Divya Fernandez  
Kolkata and its unending supply of legendary fresh fish-did you ever imagine this had any connection with the sewage generated by this overcrowded city? Well, its true – Kolkata has the world’s largest collection of fish farms fed by sewage water!  Large areas of vegetables are grown on garbage and paddy fields are irrigated by sewage effluent.
All this at the East Kolkata wetlands at the edge of the city – a place few people, even Kolkatans, have bothered to visit.
When I first heard about it, my reaction was, “Oh, must be a mucky, smelly swampy place.” When I actually went deep into the wetlands, walking along the bunds, guided by Bonanidi who has been here hundreds of times and fought a case for it back in 1992, it simply took my breath away.
You have to see it to believe it. And it didn’t look dirty at all. A network of small square cut ponds, edged with water hyacinth, paddy fields soaked in water, all interspersed by bunds, little bamboo bridges, tree-lined canals. You forget you were just half an hour ago in a big bustling city like Kolkata.
I felt humbled, but I was truly humbled when I saw people – yes human beings – living in an intricate relationship with these wetlands as if their life depended on it. It is their forefathers who helped build the wetland as it is today and has been nourished from generation to generation.
The region is part of the mature delta of the River Ganga and the wetlands are the interdistributory marshes in the delta.
The streams which were once active became inactive after the shifting of the main river and consequent loss of headwaters from the Hoogly. The tidal action of the Bay of Bengal earlier caused salinity and tides in these lake areas.
The earliest known accounts of these Salt Lakes go back to the year 1748 when it was a vast area, teeming with fish and birds and extending right up to a mound known as Dumduma, near which Burmese and Mug traders arriving in boats used to anchor.
The East Kolkata Wetlands as it is known today comprise nearly 115 sq km. Using the purification capacity of wetlands, Kolkata has pioneered a system of waste disposal that is both efficient and environment friendly, at no extra cost. The cost of setting up a sewage treatment plant today would be about Rs 400 crore and require Rs 1,000 crore in yearly maintenance.
Kolkata, the second largest Indian city containing 14 million people generates roughly 680 million litres of sewage. One-third of the city’s sewage and most of its garbage is converted into 20 tonnes of fish and 50 tonnes of vegetables.
This provides for about 60 g of fish  and 300 g of vegetables daily for about 5 lakh people.The wetland foliage has spongy roots that can accumulate heavy metals in their tissues at 100,000 times the concentration in the surrounding water and also house nurseries of fish among them.
Eichhornia crassipes or water hyacinth found here, is known as the Jekyll and Hyde of the wetland world because though it helps remove toxic materials in some wetlands it is often a costly adversary in others because of its phenomenal growth. In the East Kolkata Wetlands, the fishermen prevent the hyacinth that edges their bheris (The fishermen use gates to direct the foul smelling sewage into their tiny shallow water fishponds called bheris) from clogging the ponds by ingeniously and simply holding them back with bamboo fences. 
Rare mammals like the Indian marsh mongoose, small Indian mongoose , palm civet, and small Indian civet are found in and around the area. Threatened reptiles like the Indian mud turtle are found. Birdwatchers regularly come to watch the local as well as migratory birds that visit the wetlands. More than 40 species including coot, grebe, darter, shag, teals, cormorant, egrets, gulls, jacanas, snipes, tern, eagle, sandpiper, rails and kingfishers are seen here.
One-fourth of Kolkata’s total requirement of vegetables reach the city with minimum cost of transport. Fish reach the stalls straight from the auction market – there is no expense on cold storage or fish feed, Yet Kolkatans are ready to pay a good price because they can see how fresh it is.
Not many city dwellers realise that these wetlands are the lungs and kidneys of Kolkata. Over the years, people have been eyeing this area as free space – whether for building an eye hospital or as a place for old cows and goats!
They even wanted to build a World Trade Centre in the middle of the wetland! In 1992, the Kolkata High Court designated 12,500 ha of the wetland as a conservation area, after the judge himself visited the area. Like I said, seeing is believing!
The court order prevents changes in landuse. Yet developers encroach on its edges and development speculation never ceases to dog the area, with an active promoter-real-estate-developer lobby waiting in the wings. 
Now Dipayan Dey, environmentalist and LEAD India finalist, through the Indian chapter of the NGO SAFE is working on a project that aims to restore to restore and develop the East Kolkata Wetlands so that this precious habitat remains intact and also help sustain the communities that depend on it.
Keeping in mind that the beauty of the wetlands attracts many tourists who come for bird watching, boating, picnicking and photography, with the help of the local community, they have put together thatched huts, which are rented out to visitors. Women of the fishing communities have been trained in hospitality and catering and the families will provide these services to eco-tourists for a reasonable charge. In this way the ecosystem is taken care of while also sustaining the community.
This area is internationally recognised as the only Ramsar entry from India for wetland wise use and the only one that is by the side of a city. The people of the wetlands do not care about all this, they only want to be allowed to coexist with nature. Though Kolkata may not be aware of its lungs and kidneys, for these people, it is their very life.

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Cyclone Aila cripples East


Cyclone Aila cripples East
While Orissa faced the full wrath of the cyclone, Bengal puts up a brave challenge
Avishek Rakshit
Friday, May 29, 2009

©DQChannels

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Article from The Hindu: Sent to you by Soumya

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This article has been sent to you by Soumya ( soumyanath.c@gmail.com )
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Source: The Hindu (http://www.hinduonnet.com/2009/05/27/stories/2009052759951000.htm)
Front Page
  

West Bengal cyclone death toll mounts to 82

Ananya Dutta

Heavy rain triggers landslips in Darjeeling; Aila weakens into depression and causes downpour

— Photo: Arunangsu Roy Chowdhury

Flood of woes: Marooned villagers at Basanti in West Bengal’s South 24 Parganas district move to safer places on Tuesday.

KOLKATA: The city and some districts, devastated by cyclone Aila on Monday, are yet to come to terms with the reality, even as the death toll shot up to 82. Fresh areas in the north were reeling under the impact of the cyclone’s after-effects on Tuesday. More than 2.2 million people have been affected.
Heavy and incessant rain in Darjeeling triggered landslips, which claimed nine lives. At least six people are reported missing. The highway connecting the hills to the rest of the State was blocked at several places.
“Cyclone Aila has weakened into a depression,” said G.C. Debnath, director, weather section, Regional Meteorological Centre. “It caused very heavy rainfall in north Bengal on Tuesday.”
Chief Minister Buddhadeb Bhattacharjee has apprised Prime Minister Manmohan Singh of the situation.
Governor Gopalkrishna Gandhi, who is in Darjeeling, was in constant touch with Mr. Bhattacharjee. He visited three areas worst hit by the landslips and met the injured who were admitted to the district hospital. He appreciated the locals for their help in clearing the roads of debris.
While Kolkata limped back to normal, vast areas of the districts hit by the cyclonic storm on Monday were under water that gushed in through breaches in the embankments.
Army and Border Security Force personnel are assisting in rescue operations in Darjeeling and North and South 24 Parganas districts. Two MI-17 helicopters of the Air Force are airdropping relief materials and carrying out evacuations in inaccessible areas in South and North 24 Parganas.
More than 41,000 people, who have lost their homes, have been put up in 109 relief camps. Around 61,000 houses have been destroyed and 1.32 lakh partially damaged, Chief Secretary Ashok Mohan Chakraborty said here.
Certain areas, including Patharpratima in South 24 Parganas district, remain inaccessible.
The Chief Minister visited some of the worst-hit areas in the district. So did Trinamool Congress chief and Railway Minister Mamata Banerjee later in the afternoon.
Mr. Bhattacharjee spoke to a section of those sheltered in the relief camps in the Nimpith area. Rescue and relief operations were being undertaken on a war-footing, he said. Attempts were being made to restore power and drinking water was also being supplied in pouches.
Ms. Banerjee suggested that a master plan be drawn up for flood and erosion control. She criticised the State government for not opening adequate relief camps.
Kolkata, much to the relief of its residents, woke up to clear skies in the morning. Though traffic was back on the roads, several stretches continue to remain blocked by uprooted trees.

63 dead in Bangladesh

Haroon Habib
reports from Dhaka:
Cyclone Aila, which crossed over to Bangladesh, claimed more than 60 lives there, with more than a 100 missing as on Tuesday.
The cyclone wreaked havoc in Satkhira, a south-west district adjoining West Bengal, leaving 20 dead, said a senior official at the district control room. Packing winds of up to 110 kmph, the storm made landfall between midday and late night on Monday.
Thousands were shifted to emergency shelters along the south-west coastline. Tidal surges damaged nearly a dozen flood-control structures, marooning thousands.
Reports said many smaller islands such as Dhalchar, Char Kukrimukri, Char Patila, Char Hasina, Char Nizam and Char Kashpia in the Bay of Bengal were under 8 to 10 feet of water.

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