Introduction:

The daily use of electronic equipments are known as consumer electronics and includes TV, telephone, DVD, CD, PC, laptop etc. These equipments are manufactured throughout the world. With the advancement in electronic engineering at a continuous pace, a number of new variety electronics items flood into the market every year and the cost the existing products reduces continuously and it is one of the biggest advantage of consumer electronics industry.

Electronic waste is one of the problems associated with these electronic item and many manufacturers are now planning to deal with these waste.

Semiconductor:

All electronic devices use semiconductors and without these semiconductors none of the electronic device is complete. Semiconductor behaves like an insulator at absolute zero (-273 degree centigrade) and can be distinguished from conductor that at this temperature the outermost filled electron energy band is completely filled in a semiconductor compare to the conductor in which the band is partially filled.

At room temperature semiconductor show a very small electrical conductivity much lower than that of conductor.

Doping in semiconductor:

Most common semiconductors used for electronic devices are silicon and germanium. Although some other conductors such as iridium phosphide, gallium arsenide and mercury cadmium telluride are also used.

A pure semiconductor also known as intrinsic semiconductor, when doped with electron rich element e.g. arsenic or electron deficient element e.g. boron in very small quantity, its conductivity increases and the resultant conductor is known as extrinsic conductor. My doping arsenic (electron rich) and boron (electron deficient) in silicon, we get n-type (negative type) and p-type (positive type) semiconductor devices.

We may create a p-n junction by doping different element in different region of semiconductor and the device is known as diode. Similarly we can create p-n-p or n-p-n junctions and the device is known as triodes.

Electronic Devices

(a) Television:
It is a device by which we can receive moving pictures and sounds over a distance. The whole transmission and receiver systems require the following inputs.
1.Camera for live images or flying spot scanner for transmission of films and sound source.

2.Transmitters for transmitting both images and sounds.

3.Receiver systems for receiving these signals.

4.Display device, which is either CRT, Rear projection, LCD or plasma. To display the signal in the forms of images and sounds.

(b) Telephone:

It is the device for communicating by which two persons can send and receive sound signals over a distance. The system requires the following inputs.

1.The telephone equipment, which converts sound signals to electrical signals and electrical signals to sound signals.

2.Central exchange from where the subscribers are interconnected.

3.Wiring for connecting all the subscribers.

(c) Calculators:

It is a device used for carry out various mathematical calculations. The input required for calculator are as given below.

1.Power source (battery or solar panel).

2.Display device (LED or LCD)

3.Keypad containing all functions and numbers.

4.All electronic circuit devices.

Electronic Waste:

These are the waste electronic devices and if properly utilized may be valuable secondary raw material source for various electronic equipments and if thrown out may act as toxic due to presence of various toxic materials including lead, mercury, cadmium, arsenic etc. uncontrolled burning of these materials may also cause environmental problems.

Electronic waste is sometimes illegally sent to other countries for processing. However, due to complexity and difficulties in recycling, e-waste will remain an issue for the coming days.

Henry writes about Consumer electronics on http://www.usnag.com

Article Source: http://www.articlegarden.com

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PROTECT BIODIVERSITY

Current rates of species loss are 100-1,000 times greater than those observed in the fossil record. Loss of habitat, overfishing, and pollution are some of the major reasons for current declines in biodiversity, but humans can choose to reverse the trend.
Buy Forest Stewardship Council (FSC) certified products. Forest products with the FSC logo come from a certified well-managed forest meeting specific environmental, social and economic criteria.

Buy organic produce. Organic farmers are not allowed to use the synthetic pesticides and agricultural chemicals that pollute the environment.

Eat less meat. Intensive animal farming consumes lots of energy and water, is a growing source of pollution, and leads to land degradation. Try incorporating one meat-free day into your week.

Pick fish carefully. Many of the world’s fisheries are are decimated, in decline, or threatened by overfishing. Consult a seafood guide shuch as the Monterey Bay Aquarium’s seafood guide, the Audubon Society’s Living Oceans guide, or the Blue Ocean Institute’s guide to find out which species to avoid. If you enjoy salmon, look for the Marine Stewardship Council certified mark.

Use pesticides and herbicides sparingly. Many plants and insects serve as natural deterrents to weeds and garden pests. Introduce ladybugs to eat aphids or plant marigolds to deter beetles.

RELATED LINKS:

Green Building

Calculate Your Ecological Footprint

Climate Change Information

EPA Recycling Site

Water Information (family water audit)

From: Earth Trends

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USE LESS ENERGY

Fundamental to global warming is the amount of greenhouse gases we produce, principally from the burning of fossil fuels. Reducing energy use reduces emissions, and also saves you money!
Buy compact fluorescent bulbs for your most used lights. Although they cost a little bit more, they save money in the long run by using only one-quarter of the energy of an ordinary light bulb and lasting 8-12 times longer. (Each bulb saves 500 lbs. of CO2 per year)

Make small changes to your thermostat. Move your thermostat down 2 degrees in the winter and up 2 degrees in the summer. Wear an extra sweater if you feel cold instead of turning up the heat. (Saves 2000 lbs./year)

Insulate your walls and ceilings. Ask your utility company for a free home energy audit to find out where your home is poorly insulated or energy-inefficient. (Saves 2,000 lbs./year)

Unplug unused electronics. These devices consume energy even when turned off. (Saves 1,000 lbs./year)

Buy energy-efficient appliances. When you are shopping for a new home appliance, look for designations of high energy efficiency, such as the energy star label.

Wash clothes in cold or warm water, not hot. (Two loads per week saves 500 lbs./year)

Turn down your water heater. 120 degrees F is hot enough for most households. Turn it off completely when you go on vacation. (Each 10-degree adjustment saves 500 lbs./year)

Monitor your refrigerator. Refrigerators account for roughly 20% of household energy use. A reasonable temperature is 37 degrees F, and 3 degrees F for the freezer.

Use your car efficiently. Lighten your vehicle’s load by clearing out the trunk, drive smoothly to avoid braking, make sure your tires are properly inflated, and have your car serviced regularly. Don’t make unnecessary trips. (Inflating your tires saves 250 lbs./year)

Use transportation alternatives. Walk, bike, carpool, or use public transportation as much as possible.

Support local farmers. A lot of energy is wasted by preserving and shipping food around the world. Buy your produce from a local farmers’ market to cut down on transportation costs. Find one near you at www.localharvest.org/csa.

Offset your CO2 emissions.

First, find out how much CO2 you are emitting each year using one of several available carbon calculators. For example:

• World Resources Insitute’s Safe Climate
• ClimateCrisis.net (For U.S. Only)
• ClimateCare
• CarbonFund.org
• Conservation International
• or see the EarthFuture calculator list

A donation to any number of national and international carbon-offset organizations (including those listed above) will typically be used to invest in renewable energy initiatives and/or plant or preserve an amount of forest that is CO2-equivalent to your emissions, thus reducing your personal contribution to global warming.

You can even travel in a sustainable way. See:

• Sustainable Travel International; or
• Offset your CO2 emissions from air travel by using TerraPass (also available when purchasing tickets through Expedia.com).

From: Earth Trends

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REDUCE THE AMOUNT OF WASTE YOU PRODUCE

The average person in an industrialized country produces over 4 pounds of garbage per day. Solid waste is a significant source of pollution, and being wasteful also has serious implications for energy use and global warming. Recycling just one aluminum saves enough energy to run a television for three hours!
Recycle and reuse. Roughly 50% of the average person’s trash can be recycled. Don’t forget that hazardous waste like batteries, your printer’s ink cartridges, and cell phones can be recycled too! Find out how and where to recycle in your area. Always buy recycled paper. Just 1 ton of recycled paper saves 17 trees.

Bring your own grocery bags when you shop. Designate a reusable cloth sack as your grocery bag and use neither paper nor plastic. If you are buying something small, carry it home in your pocket.

Start a compost pile. Don’t trash your kitchen and garden wastes. You can cut your household’s waste by 500 pounds per year while creating a fertile soil for your garden. Learn more about how to start composting.

Buy products with less packaging. About 33% of municipal waste is packaging. When choosing between two products, pick the one with the least amount of unnecessary packaging. Reuse packaging when possible.

Avoid using throw-away products. Paper napkins, plastic silverware, and paper plates are easily replaced by reusable alternatives. Store food in reusable containers instead of using plastic bags, aluminum foil, or plastic wrap.

From: Earth Trends

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People often ask, “What can I do?” So we’ve compiled a list to help give you a place to start… Please, do your part. Global issues like poverty, climate change, and biodiversity loss are not only the part of third world countries to deal with, repair, or be responsible for. And if we’re not part of the solution, we are part of the problem. There is simply no sitting on the fence on this one.

While I realize that this list is far from complete or all-encompassing, it is a start and if you have anything to add, please contact us.
We’ll start today with what appears to be an abundant resource. It’s not.
CONSERVE WATER

Water is necessary to the survival of both people and ecosystems. Despite the apparent abundance of water in some countries, water is actually a limited resource; less than 1% of the Earth’s water is available for human use. An easy first step to conserving water is cutting down on water waste.
Repair leaky faucets. Just one drip per second wastes 20 gallons per day.

Check your toilet for leaks. Put 10 drops of food coloring in your toilet tank. If the color begins to appear in the bowl after 20 minutes without flushing, you have a leak that could be costing you 200 gallons per day. Repair parts are cheap and easy to install.

Turn off the water while brushing your teeth, shaving, or washing your face. Faucets spout 2-3 gallons per minute. Also, try installing an inexpensive faucet aerator to reduce the flow.

Take shorter showers. Showers use 5 to 10 gallons per minute. Consider buying a low flow shower head.

Put a plastic bottle in your toilet tank. If you do not own a low flow toilet, fill a plastic bottle with water or sand and place it in the tank of your toilet where it will not interfere with the operating mechanisms. This will decrease the amount of water used with each flush.

Run the washing machine and dishwasher only when full. If you have to wash a partial load, adjust the water level settings accordingly and avoid the permanent press cycle, which uses an extra 5 gallons. If you are buying a new appliance, consider a water-saving front load washer.

Don’t let the water run while washing dishes. Fill up the sink basin or a large bowl for washing and run the faucet at a low level for rinsing.

Turn off the water while you wash your car. Use a bucket instead and save over 100 gallons.

Water your lawn only when it needs it. If the grass springs back up after you step on it, it doesn’t need water. Try to water during the cool parts of the day and avoid watering when it is windy.

Use recycled water for your houseplants. Save the leftover water from boiling eggs, washing vegetables, etc.

From:  Earth Trends

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