Category Archives: Science

Hypermiling : Ways to decrease your fuel consumption

From Hypermiling

1. First (and most important) step: Start recording your gas mileage. Easiest way? Use your trip odometer. Method to check your MPG

2. Second step: Do you drive aggressively and not know it?

3. The third step: How long are you sitting still at red lights?

4. The fourth step: Keeping moving in traffic congestion.

5. The fifth step: Slowly accelerate after stops.

6. The sixth step: Your cruise control saves gas (but not by using it they way you might think)

Cheap Drinking Water from the Ocean

Carbon nanotube-based membranes will dramatically cut the cost of desalination.
By Aditi Risbud

A water desalination system using carbon nanotube-based membranes could significantly reduce the cost of purifying water from the ocean. The technology could potentially provide a solution to water shortages both in the United States, where populations are expected to soar in areas with few freshwater sources, and worldwide, where a lack of clean water is a major cause of disease.

The new membranes, developed by researchers at Lawrence Livermore National Laboratory (LLNL), could reduce the cost of desalination by 75 percent, compared to reverse osmosis methods used today, the researchers say. The membranes, which sort molecules by size and with electrostatic forces, could also separate various gases, perhaps leading to economical ways to capture carbon dioxide emitted from power plants, to prevent it from entering the atmosphere.

The carbon nanotubes used by the researchers are sheets of carbon atoms rolled so tightly that only seven water molecules can fit across their diameter. Their small size makes them good candidates for separating molecules. And, despite their diminutive dimensions, these nanopores allow water to flow at the same rate as pores considerably larger, reducing the amount of pressure needed to force water through, and potentially saving energy and costs compared to reverse osmosis using conventional membranes.

Indeed, the LLNL team measures water flow rates up to 10,000 times faster than would be predicted by classical equations, which suggest that flow rates through a pore will slow to a crawl as the diameter drops. “It’s something that is quite counter-intuitive,” says LLNL chemical engineer Jason Holt, whose findings appeared in the 19 May issue of Science. “As you shrink the pore size, there is a huge enhancement in flow rate.”

The surprising results might be due to the smooth interior of the nanotubes, or to physics at this small scale — more research is needed to understand the mechanisms involved. “In some physical systems the underlying assumptions are not valid at these smaller length scales,” says Rod Ruoff, a physical chemist and professor of mechanical engineering at Northwestern University (who was not involved with the work).

To make the membranes, the researchers started with a silicon wafer about the size of a quarter, coated with a metal nanoparticle catalyst for growing carbon nanotubes. Holt says the small particles allow the nanotubes to grow “like blades of grass — vertically aligned and closely packed.” Once grown, the gaps between the nanotubes are filled with a ceramic material, silicon nitride, which provides stability and helps the membrane adhere to the underlying silicon wafer. The field of nanotubes functions as an array of pores, allowing water and certain gases through, while keeping larger molecules and clusters of molecules at bay.

Holt estimates that these membranes could be brought to market within the next five to ten years. “The challenge is to scale up so we can produce usable amounts of these membrane materials for desalination, or gas separation, the other high-impact application for these membranes,” he says, adding that the fabrication process is “inherently scalable.”

Eventually, the membranes could be adapted for a variety of applications, ranging from pharmaceuticals to the food industry, where they could be used to separate sugars, for example, says co-author Olgica Bakajin, a physicist at LLNL. “Practically, the next step is figuring out how to take a general concept and modify it to a specific application,” Bakajin says.

“There are many studies that one can imagine to build upon this study,” says Northwestern’s Ruoff. “Our understanding of molecular processes will be helped by experiments of this type. There are interesting possibilities for nanofluidic applications, such as in nanoelectromechanical systems and in ‘smart’ switching [on and off] of the flow through such small channels.”

How to listen

from Communication Nation

Great communicators are great listeners. They pay attention and ask questions until they gain a deep and textured understanding of whatever situations they find themselves in.

An intellectual understanding is not enough: great communicators listen till they feel it. They empathize.

If you want to be a better communicator learn to listen, and more importantly, listen to learn.

As you talk to people, make it a habit to continuously check to confirm that you are understanding them correctly. The more questions you ask, the less tempted you will be to preach or prescribe solutions. How would you feel if your doctor prescribed medication before asking you about your symptoms? The more people talk to you, the more they will feel understood, and the more they will like you.

Here are the ten commandments of good listening:

1. Empty your mind. Try to begin with a blank slate. This will help you stay open to things you don’t expect — one of the most powerful things listening can do is open your mind to new ideas or reveal things that were formerly hidden.

2. Understand the context. Try to figure out what the person is trying to communicate and why. This will help you act in a manner that’s appropriate to the context, and ask the right questions.
– Are they just venting or do they want to change something?
– What problem do they want to solve?
– What result do they want?
– Do they want you to do something? If so, what?

3. Don’t get distracted. Your mind will have a natural tendency to wander, because we can think faster than people can talk. Knowing your your learning style can help: Are you visual (learn by seeing), auditory (learn by hearing) or kinesthetic (learn by doing)?

4. Use follow trails. A follow trail is a simple question that you can keep asking till you get to the root of something. Just continue to ask the question till you get to the source. You’ll be surprised how powerful this one is. Here are some examples of follow trail questions:
– And?/and?
– Why?/why?
– How?/how?

5. Use body language. Your physical behavior signals how well you’re communicating. The most important signal is your eyes. Make steady eye contact and focus on the person’s face. Nodding and leaning forward also signal attention.

6. Ask questions. Like a good detective, the art is in asking the right questions, and asking them well.

7. Take notes. It demonstrates that what the person is saying is important enough for you to write it down. Occasionally, verbally summarize your notes out loud, to show the other person you are hearing and understanding them.

8. Confirm your understanding. As you listen, think about how the person’s thoughts would work in practice. play out scenarios in your mind and ask the person to confirm your understanding. For example, ask the person:
– “So if I were to apply this, I would…”
– “So what you are saying is…”

9. Let the person finish before you speak. We listen and process information faster than people can talk — this can result in reacting or answering before someone is finished speaking — your mind is racing ahead. Not to mention it’s rude. Don’t interrupt.

10. Don’t judge too quickly. Suppress your own reactions — remember to maintain that blank slate in your mind. Reserve judgment till the end of the conversation (or even later). If you keep an open mind you will reap the full benefit of the conversation and if you don’t, you are limiting its potential.

Next time you communicate — whether it’s with an individual or with agroup — diagnose before you prescribe. The results will amaze you.

Listening skills

The average college student spends about 14 hours per week in class listening (or perhaps I should say “hearing“–there is a difference!) to lectures. See if you can improve your listening skills by following some of the strategies below:

Maintain eye contact with the instructor. Of course you will need to look at your notebook to write your notes, but eye contact keeps you focused on the job at hand and keeps you involved in the lecture.

Focus on content, not delivery. Have you ever counted the number of times a teacher clears his/her throat in a fifteen minute period? If so, you weren’t focusing on content.

Avoid emotional involvement. When you are too emotionally involved in listening, you tend to hear what you want to hear–not what is actually being said. Try to remain objective and open-minded.

Avoid distractions. Don’t let your mind wander or be distracted by the person shuffling papers near you. If the classroom is too hot or too cold try to remedy that situation if you can. The solution may require that you dress more appropriately to the room temperature.

Treat listening as a challenging mental task. Listening to an academic lecture is not a passive act–at least it shouldn’t be. You need to concentrate on what is said so that you can process the information into your notes.

Stay active by asking mental questions. Active listening keeps you on your toes. Here are some questions you can ask yourself as you listen. What key point is the professor making? How does this fit with what I know from previous lectures? How is this lecture organized?

Use the gap between the rate of speech and your rate of thought. You can think faster than the lecturer can talk. That’s one reason your mind may tend to wander. All the above suggestions will help you keep your mind occupied and focused on what being said. You can actually begin to anticipate what the professor is going to say as a way to keep your mind from straying. Your mind does have the capacity to listen, think, write and ponder at the same time, but it does take practice.

Scientists target poor to test sludge theory

from the Cape Cod Times.

By JOHN HEILPRIN and KEVIN S. VINEYS

BALTIMORE — Scientists using federal grants spread fertilizer made from human and industrial wastes on yards in poor, black neighborhoods to test whether it might protect children from lead poisoning in the soil.

Families were assured the sludge was safe and were never told about any harmful ingredients.

Nine low-income families in Baltimore row houses agreed to let researchers till the sewage sludge into their yards and plant new grass. In exchange, they were given food coupons as well as the free lawns as part of a study published in 2005 and funded by the Housing and Urban Development Department.

The Associated Press reviewed grant documents obtained under the Freedom of Information Act and interviewed researchers. No one involved with the $446,231 grant for the two-year study would identify the participants, citing privacy concerns.

There is no evidence there was ever any medical follow-up.

Comparable research was conducted by the Agriculture Department and Environmental Protection Agency in a similarly poor, black neighborhood in East St. Louis, Ill.

The sludge, researchers said, put the children at less risk of brain or nerve damage from lead, a highly toxic element once widely used in gasoline and paint. Other studies have shown brain damage among children, often in poor neighborhoods, who ate lead-based paint that had flaked off their homes.

The idea that sludge — the leftover semisolid wastes filtered from water pollution at 16,500 treatment plants — can be turned into something harmless, even if swallowed, has been a tenet of federal policy for three decades.

In a 1978 memo, the EPA said sludge “contains nutrients and organic matter which have considerable benefit for land and crops” despite the presence of “low levels of toxic substances.”

But in the late 1990s the government began underwriting studies such as those in Baltimore and East St. Louis using poor neighborhoods as laboratories to make a case that sludge may also directly benefit human health.

Meanwhile, there has been a paucity of research into the possible harmful effects of heavy metals, pharmaceuticals, other chemicals and disease-causing microorganisms often found in sludge.

A series of reports by the EPA’s inspector general and the National Academy of Sciences between 1996 and 2002 faulted the adequacy of the science behind the EPA’s 1993 regulations on sludge.

The chairman of the 2002 academy panel, Thomas Burke, a professor at the Johns Hopkins Bloomberg School of Public Health, says epidemiological studies have never been done to show whether spreading sludge on land is safe.

“There are potential pathogens and chemicals that are not in the realm of safe,” Burke told the AP. “What’s needed are more studies on what’s going on with the pathogens in sludge — are we actually removing them? The commitment to connecting the dots hasn’t been there.”

That’s not what the subjects of the Baltimore and East St. Louis research were told.

Rufus Chaney, an Agriculture Department research agronomist who co-wrote the Baltimore study, said the researchers provided the families with brochures about lead hazards, tested the soil in their yards and gave assurances that the Orgro fertilizer was store-bought and perfectly safe.

“They were told that their lawn, as it stood, before it was treated, was a lead danger to their children,” said Chaney. “So that even if they ate some of the soil, there would not be as much of a risk as there was before. And that’s what the science shows.”

Chaney said the Baltimore neighborhoods were chosen because they were within an economically depressed area qualifying for tax incentives. He acknowledged the families were not told there have been some safety disputes and health complaints over sludge.

“They were told that it was composted biosolids that are available for sale commercially in the state of Maryland. I don’t think there’s any other further disclosure required,” Chaney said. “There was danger before. There wasn’t danger because of the biosolids compost. Composting, of course, kills pathogens.”

The Baltimore study concluded that phosphate and iron in sludge can increase the ability of soil to trap more harmful metals including lead, cadmium and zinc, causing the combination to pass safely through a child’s body if eaten.

It called the fertilizer “a simple low-cost” technology for parents and communities “to reduce risk to their children” who are in danger of lead contamination. The results were published in Science of the Total Environment, an international research journal, in 2005.

Another study investigating whether sludge might inhibit the “bioavailability” of lead — the rate it enters the bloodstream and circulates to organs and tissues — was conducted on a vacant lot in East St. Louis next to an elementary school, all of whose 300 students were black and almost entirely from low-income families.

In a newsletter, the EPA-funded Community Environmental Resource Program assured local residents it was all safe.

“Though the lot will be closed off to the public, if people — particularly children — get some of the lead contaminated dirt in their mouths, the lead will just pass through their bodies and not be absorbed,” the newsletter said. “Without this iron-phosphorus mix, lead poisoning would occur.”

Soil chemist Murray McBride, director of the Cornell Waste Management Institute, said he doesn’t doubt that sludge can bind lead in soil.

But when eaten, “it’s not at all clear that the sludge binding the lead will be preserved in the acidity of the stomach,” he said. “Actually thinking about a child ingesting this, there’s a very good chance that it’s not safe.”

McBride and others also questioned the choice of neighborhoods for the studies and why residents were not told about other, possibly harmful ingredients in sludge.

“If you’re not telling them what kinds of chemicals could be in there, how could they even make an informed decision. If you’re telling them it’s absolutely safe, then it’s not ethical,” McBride said. “In many relatively wealthy people’s neighborhoods, I would think that people would research this a little and see a problem and raise a red flag.”

The Baltimore study used a compost of sludge mixed with sawdust and wood chips packaged as “biosolids,” the term for sludge preferred by government and the waste industry.

“What we did was make the yards greener,” said Pat Tracey, a Johns Hopkins University community relations coordinator who recalled helping with the lawn work. “They were bald, bad yards. It was considered sterile fertilizer.”

Baltimore environmental activist Glenn Ross says choosing poor neighborhoods destined for demolition makes it hard to track a study’s participants. “If you wanted to do something very questionable, you would do it in a neighborhood that’s not going to be there in a few years,” he said.

HUD documents show the study’s lead author, Mark Farfel, has pursued several other studies of lead contamination including the risks of exposure from urban housing demolitions and the vacant lots left behind.

Farfel has since moved to New York, where he directs the World Trade Center Health Registry surveying tens of thousands of victims of the Sept. 11 attacks. He denied repeated requests for interviews and referred questions to Baltimore’s Kennedy Krieger Institute, the children’s research facility that was the recipient of HUD grants with Farfel as project manager.

The institute referred questions to Joann Rodgers, a spokeswoman for Johns Hopkins. She said a review board within its medical school approved the study and the consent forms provided to families that participated. “The study did not test children or other family members living in the homes,” she said.

Some of Farfel’s previous research has been controversial.

In 2001, Maryland’s highest court chastised him, Kennedy Krieger and Johns Hopkins over a study bankrolled by EPA in which researchers testing low-cost ways to control lead hazards exposed more than 75 poor children to lead-based paint in partially renovated houses.

Families of two children alleged to have suffered elevated blood-lead levels and brain damage sued the institute and later settled for an undisclosed amount.

The Maryland Court of Appeals likened the study to Nazi medical research on concentration camp prisoners, the U.S. government’s 40-year Tuskegee study that denied treatment for syphilis to black men in order to study the illness and Japan’s use of “plague bombs” in World War II to infect and study entire villages.

“These programs were somewhat alike in the vulnerability of the subjects: uneducated African-American men, debilitated patients in a charity hospital, prisoners of war, inmates of concentration camps and others falling within the custody and control of the agencies conducting or approving the experiments,” the court said.
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On the Net:
Baltimore study: http://tinyurl.com/3g2e3q
East St. Louis project: http://tinyurl.com/43s3qx
Maryland lead lawsuit: http://tinyurl.com/4ydssm
National Academy of Sciences’ report: http://tinyurl.com/4esxjv

Ten Greatest Pictures Taken by Hubble

1. The Sombrero Galaxy – 28 million light years from Earth – was voted best picture taken by the Hubble telescope. The dimensions of the galaxy, officially called M104, are as spectacular as its appearance. It has 800 billion suns and is 50,000 light years across.

2. The Ant Nebula, a cloud of dust and gas whose technical name is Mz3, resembles an ant when observed using ground-based telescopes. The nebula lies within our galaxy between 3,000 and 6,000 light years from Earth.

3. In third place is Nebula NGC 2392, called Eskimo because it looks like a face surrounded by a furry hood. The hood is, in fact, a ring of comet-shaped objects flying away from a dying star. Eskimo is 5,000 light years from Earth.

4. At four is the Cat’s Eye Nebula

5. The Hourglass Nebula, 8,000 light years away, has a pinched-in-the-middle look because the winds that shape it are weaker at the center.

6. In sixth place is the Cone Nebula. The part pictured here is 25 light years in length (the equivalent of 23 million return trips to the Moon).

7. The Perfect Storm, a small region in the Swan Nebula, 5,500 light years away, described as ‘a bubbly ocean of hydrogen and small amounts of oxygen, sulphur and other elements’.

8. Starry Night, so named because it reminded astronomers of the Van Gogh painting. It is a halo of light around a star in the Milky Way.

9. The glowering eyes from 114 million light years away are the swirling cores of two merging galaxies called NGC 2207 and IC 2163 in the distant Canis Major constellation.

10. The Trifid Nebula. A ‘stellar nursery’, 9,000 light years from here, it is where new stars are being born.