Posted on 20 July 2011.
Posted in What Is/Are...?Comments Off
Posted on 16 July 2011.
A bubble is a globule of one thermodynamic phase inside of another, like a gas in a liquid. We commonly find bubbles in boiling water, carbonated sodas, sea foam, and gas pockets in glass. Learning about bubbles can teach us about many concepts, like shape, transparency, mirrored surfaces, colors, and flexibility.
Bubbles are produced by the scientific process of nucleation. Nucleation occurs when a small pocket of one thermodynamic phase forms inside of another. In bubbles, the thermodynamic phase of a gas forms inside of the thermodynamic phase of a liquid. However, pure water is not stable enough to produce a lingering bubble. We use soap to stabilize bubbles, allowing them to linger for longer. Many incorrectly believe that soap increases water’s surface tension. This is not true. In fact, soap decreases water’s surface tension. Soap does not strengthen bubbles, it merely stabilizes them.
We use bubbles in many ways, both practical and fun. We use bubbles in ultrasounds to help us better see babies. We use bubbles to better understand mathematical concepts, like minimal surface area. Performance artists use bubbles for their aesthetic properties. We also use bubbles as toys. Children have been playing with bubbles since the 1600s. Toy stores sell about two hundred million bottles of bubble mixture every year.
When disturbed, bubbles pulsate, or rapidly oscillate in size. These oscillations destabilize bubbles, leading them to eventually tear apart. The popping of bubbles below produces most of the liquid sounds that we hear.
If you would like to learn more about bubbles, you can do so by observing them yourself. Enjoy educational, fun homemade bubbles by mixing your own bubble solution. Simply combine ½ a cup of dishwashing liquid, two teaspoons of sugar, and two cups of water to make bubbles whenever you want.
Posted in Water UseComments Off
Posted on 02 July 2011.
Nowadays, after the growth of industries, clean drinking water doesn’t naturally occur. Scientists continually discover contaminants in fresh water sources and correlates between drinking contaminated water and health problems. Because we need water but it is impure, we have learned to treat water. However, the history of water filtration is not a recent one; water filtration began over 4000 years ago.
Some milestones in the history of water include the invention of the microscope, the advent of municipal water treatment, the use of chlorine to purify water, and the Clean Water Act of 1972.
The earliest recorded attempts to filter water date back to 2000 BC, to early Sanskrit writings of water purification methods. These methods include boiling water and filtering water through sand or charcoal filters. The Sanskrits’ biggest motive was to make water taste better, because they assumed that good-tasting water would also be clean. People didn’t yet realize that contaminated water caused disease, and they certainly couldn’t test for diseases in water.
In 1590, the Dutch glasses-makers Zaccharias and Hans Janssen invented the forerunner to modern-day microscopes. A century later, Anton van Leeuwenhoek, “the father of microscopy,” advanced the Janssens’ invention to the extent that scientists could now view tiny living particles in water that had previously been thought clean. In nineteenth-century London, city officials first linked cholera to bad water quality. John Snow, a British scientist, confirmed cholera bacteria in the Broad Street Pump’s water, proving that taste and visual clarity doesn’t prove water’s pureness. After this event, the British government insisted upon filtering city water, a precedent for municipal water systems. The British municipal water system cleaned water partly by treating it with chlorine.
In the 20th century, people increasingly agreed that every person has the right to clean water. The Clean Water Act (CWA) of 1972 made it a law that every city in the United States must have a water treatment plant. The CWA forced industrial plants to become environmentally friendly and renewed interest in water filtration, making clean water a national goal. Today the history of water continues as we strive to bring clean water to places that still need it.
Posted in Water UseComments Off
Posted on 01 July 2011.
The history of water treatment has been marked by slow, gradual discoveries that coincided with human development. While water filtration technology only became successful and widely used in the 20th century, the history of water treatment can be traced back to thousands of years ago.
Man has sought pure, clean water for as long as he has been on Earth. The earliest recorded mention of water filtration and purification can be found in Sanskrit writings from about 2000 B.C.E. These writings state that “impure water should be purified by being boiled over a fire…or it may be purified by filtration through sand and coarse gravel and then allowed to cool.” This demonstrates that even in some of the earliest civilizations the basics of water purification were known. There is also some evidence that the ancient Egyptians used wick siphons for water clarification. Later, following the tutelage of Hippocrates, the Greek and Roman empires used cloth bags and additives such as pounded barley to filter out bad tastes in water.
After Sir Francis Bacon renewed interest in filtration in 1627, a number of important scientific discoveries deeply affected the history of water treatment. Around 1690, Anton van Leeuwenhoek invented an early version of the modern microscope, which allowed scientists to more effectively study particles in water. Meanwhile, in Italy, Lucas Antonius Portius invented the first effective sand filtration system using multiple perforated compartments and large grains of sand. These two inventions allowed people in 19th century Britain to examine disease-causing bacteria in water and create one of the world’s first municipal water treatment systems.
In the early 1900s, English physicians discovered that chlorine was very effective in eliminating disease from water, and chlorination of public water systems began. The United States and other countries soon followed suit, and in 1972, the Environmental Protection Agency passed the Clean Water Act, requiring cities to filter public water. Today, amid growing concerns about the safety of water fluoridation and chlorination, individual households have begun to install filtration devices to taps, showerheads, and entire plumbing systems.
The history of water filtration is still being written. While individuals in America and other countries continue to improve the quality of household water, many people in developing countries lack the ability to properly filter their water. The challenge moving forward will be in improving water filtration for all of humanity.
Posted in SanitationComments Off
Posted on 28 June 2011.
Another irrigation system, drip irrigation, waters more precisely. Drip irrigation, also known as micro-irrigation or trickle irrigation, uses very thin plastic tubes, usually called drip tape, with small holes every few feet. These tiny holes usually release only a drop of water at a time. The grower lays the drip tape across the field alongside the plants and matches the small holes in the tape with the plants. When water is pumped through the drip tape, the drip system slowly waters each plant. This method prevents water loss to runoff. The system pumps the water directly into the ground, preventing the diseases that can occur when leafy material touches water. The drip tape is often buried an inch under the earth in order to protect the tape from tractors and to decrease the amount of water lost to evaporate. However, a drip irrigation system is expensive, and may cost over a thousand dollars per acre. Also, the drip tape can be easily clogged, requiring maintenance.
Posted in OutdoorsComments Off
Posted on 25 March 2011.
Many people hear about hard and soft water without really knowing what those terms mean. Understanding how water is classified lets a homeowner make an informed choice when it comes to the family drinking water and general household water supply. Some people absolutely love soft water, while others strictly prefer the qualities of hard water.
Hard water contains naturally occurring concentrations of calcium, lime and magnesium. This can be seen in the residue that hard water can leave behind on surfaces like shower walls and sinks. Soft water, on the other hand, is treated to only contain ions of sodium, giving soft water a slightly salty taste. Because of this, people may notice a subtle difference in the tastes of hard and soft water.
Both types of water originate with rainwater that filters through underground rocks. Water becomes ‘hard’ when the water passes through soft, loose rock containing minerals and calcium that easily break apart and are carried into the water flow. In contrast, soft water passes through hard granite rock, picking up very trace amounts of minerals.
Some homeowners prefer soft water because the lack of mineral content keeps their kitchen appliances and plumbing from requiring extra maintenance, while lengthening their life spans. Hard water deposits are also harder to clean from surfaces in the bathroom and kitchen.
Bathing in soft water has the added health benefit of leaving hair clean without stripping it of important natural oils. It’s also known to be beneficial for those with sensitive or breakout-prone skin, as soft water does not clog pores like hard water can.
According to studies done by the National Research Council, there is no evidence that drinking hard water can cause adverse health issues, but can instead be beneficial. Drinking hard water that contains small amounts of calcium and magnesium can be valuable to those who don’t get enough of these minerals by daily diet alone. As such, for health benefits, hard water is more often recommended as the drinking water of choice.
The easiest way to tell if water is hard or soft is to look for residue on surfaces. White, scaly residue or even green discoloration around water pipes means calcium and lime are present in the water. Sometimes, holding a glass of tap water up to the sunlight will show the tiny particles of minerals and calcium deposits that are present in hard water. To be sure, buy a home water testing kit.
Both hard and soft water have their pros and cons and choosing between hard or soft water for drinking, bathing and household chores is a personal choice. Some families combine the best of both worlds by using hard water for drinking and soft water for bathing and washing clothes, but both are perfectly safe.
Posted on 01 March 2011.
It’s easy to not think about how much water is used to make things that we use everyday. However, besides implementing tips for water conservation, understanding how water is used to make things is important in our goal of reducing water consumption. It’s not just the water used to make stuff but also the water used for growing, processing and transporting. For example, cotton uses a tremendous amount of water to grow and to eventually become a pair of stylish jeans. Those morning lattes from the local coffeeshop use more water than is served in a given cup. And given the huge amounts of water used in manufacturing, many companies are looking for ways to reduce their water footprints.
It takes much more water to make things for the American dinner table than one would imagine. Obviously food crops need water to thrive, however, many people would be surprised to learn how much water is used to grow our food. It takes almost 20 gallons of water for one apple, 4,000 gallons for one bushel of corn and 11,000 gallons for one bushel of wheat. It takes over 15,000 gallons of water to raise a cow from birth to slaughter.
It takes an amazing 53 gallons of water to make a latte. This figure may be hard to believe given that most lattes are just over a cup. Planet Green’s Brian Merchant states in a recent article that each latte requires water for the cane sugar’s growth, the plastic lid’s manufacture, the paper cup and sleeve’s manufacture, as wells as for the transportation costs for all of the above. Hamburgers take a whopping 634 gallons of water to make mostly given the cost of raising beef.
According to OnEarth.org, it takes over 1,500 gallons of water to produce the cotton in one pair of jeans. And that’s just for growing the cotton, it doesn’t include the water used to dye jeans or to ‘weather’ them so that new jeans look and feel ‘broken in.’ It takes 400 gallons of water to grow the cotton to make one shirt. Water consumption for growing cotton crops is huge and cotton is the largest natural fiber textile in the world accounting for 40% of textile production.
Most companies know how much water it takes to make things and are looking for ways to decrease water consumption for their products and for their supply chains. For example, Levi’s has recently introduced a new brand called Water less, that reduces water usage by an average of 28% and up to 96% for some products. Water Footprint Network recommends that companies complete their water footprint assessment manual to review their water usage. It provides for a global standard on definitions and calculations how how much water we’re using.
Posted on 26 February 2011.
Many people wonder how good the water quality in their area is. When water contains contaminants, it leaves behind tiny particles that are dissolved in the water, particles that are called “total dissolved solids.” This map charts total dissolved solids in the water. Although this chart doesn’t show exactly which contaminants are present in your water and whether they’re bad for you, it’s still a good measure of water purity.
Click on the map to find out more about your local water quality.
Posted on 23 February 2011.
Fluoride in water supplies is quite a controversial topic these days. As with nearly every topic, there are two sides of the fluoride debate. Some believe fluoride to be beneficial, especially in oral health and overall costs. Others, however, believe the possible side effects of fluoride in the water to be far too risky and even unethical.
According to the Center of Disease Control and Prevention (CDC), fluorides prevents tooth decay. Bacterias from certain foods create acids which eat away the natural minerals lining the teeth. Fluoride restores the minerals, preventing further damage to the tooth, and even helping to restore damaged teeth. When it is in the water supply, teeth are repeatedly exposed to the fluoride, allowing for frequent protection. Tooth decay has become extremely prevalent, especially in children and teenagers. Half of teens, ages 12-15, have at least one cavity. Fluoridated water can be very beneficial to people of every age, as studies have shown that over a person’s lifetime, tooth decay can be reduced by 25 percent.
Due to the consistent protection teeth receive through fluoridated water, overall costs of oral health decrease. The outright cost to fluoridate water is about .50 per person, based on a city of 20,000 or more. The CDC claims that “every $1 invested in this preventive measure yields approximately $38 savings in dental treatment costs.” Fluoridated water is more cost effective than obtaining fluoride from other means, such as toothpaste or mouth washes, though these methods still provide the same protection.
Not everyone is convinced that fluoride is beneficial, however, and believe the risks and potential side effects of fluoride outweigh the benefits. Some studies show that fluoride can potentially cause cancer, lower the IQ, cause changes in bone structure and inhibit the immune system. One study in the United Kingdom showing that miscarriages and birth defects were 15 percent more likely in areas with fluoridated water, compared to those without it. Additionally, in this fluoridated city, Down’s Syndrome was 30 percent more likely. Like everything, fluoride has potential side effects, but that does not mean that these side effects will come to fruition. The CDC has deemed use of fluoride safe, though risks do still exist.
Though there are benefits to fluoride in water supplies, there are also risks to be accounted for before deciding one way or another.
Posted on 17 February 2011.
Chlorine is a common disinfectant that is widely used for water disinfection. Chlorine’s disinfecting properties has made it useful in providing clean and safe tap water for many homes and communities. However, chlorine in water also has its own set of health risks. Because of this, it is advantageous to know the different ways to remove chlorine from water or entirely replace the application of chlorine in treating water.
Chlorine in water is well known and widely used as a disinfectant. The application of chlorine is effective for deactivating various pathogenic microorganisms – mostly bacteria or viruses, which cause illness. Chlorine is usually added into public water supplies in order to kill different bacteria present in the water or the water pipes. These bacteria can be hazardous to human health. Aside from disinfecting water, chlorine is also used to disinfect various home and hospital areas and bleach fabrics. These different applications of chlorine have been in use for over two centuries.
All of the disinfecting qualities of Chlorine come with a price though. It has been identified that chlorine in water reacts with different naturally-occurring components which cause it to form into toxins called trihalomethanes (THM). There has been a connection seen between THMs and disease like asthma, eczema, heart diseases and bladder cancer. Dr. Peter Montague from the Environmental Research Foundation has enumerated a number of studies that have shown that pregnant women who drink chlorinated tap water in moderate to large amounts are at a high risk of suffering miscarriages and birth defects.
A carbon filter is proving to be an effective device for removing chlorine, toxins like THMs and other harmful contaminants from water. Another benefit of using a carbon filter is that it is cheaper compared to other electronic filters but produces the same good quality water. There is also a simpler way of removing chlorine and other compounds from water without the need for a home filtration system. This involves placing water in an uncovered container and leaving it for 24 hours inside the refrigerator.
Although resolving water contamination and cleaning up watersheds is proving to be a challenging ordeal, there are alternatives to using chlorine as a form of water treatment. Dr. Peter Montague also shares that a number of Canadian and European cities are using ozone to disinfect their water instead of chlorinating it. Cities in the United States like Las Vegas and Santa Clara are also switching to this alternative. We could all become healthier by switching away from using chlorine in water.