Why Icicles Are Long And Thin

Mathematical Physics Explains

How Icicles Grow

When droplets of melted snow drip down an icicle, they release small amounts of heat as they freeze. Heated air travels upwards and helps slow down the growth of the icicle’s top, while the tip is growing rapidly. Knowledge of the mathematical equations that govern icicle growth — the same that apply to stalactites — could help in the prevention of icicle formation on power lines.

Icicles can be dangerous and deadly, yet they can create some of the most amazing winter scenes. And for scientists, those winter scenes are playgrounds for discovery.

It’s on those playgrounds that experts in physics and mathematics are building their theories on what it takes to create an icicle.

We all know icicles form when melting snow begins dripping down a surface. But what scientists didn’t know is how their shape is formed. What makes each icicle different?

University of Arizona Physicist Martin Short turned to mathematics to find out.

“Icicles have a certain mathematical shape, and this mathematical shape is universal among icicles,” Short tells DBIS.

So what is the math behind an icicle?

“Here I’ve drawn the profile of an icicle. Here is the height, and here’s the radius … Here’s the profile here, and I’ve written the formula here. The height is proportional to the radius to the four-thirds,” he says.

What does the formula have to do with an icicle’s shape? “It kind of looks like a carrot,” says Short. “It starts out flat and then sort of up as you go.”

As water drips onto an icicle and freezes, it releases heat. The warm air rises up the sides of the icicle. Short says that warm air layer acts like a blanket that’s an insulator, and so the blanket is very thin near the tip and thick at the top. That allows the top to grow very slowly and the tip to grow rapidly — creating a long, thin icicle.

It’s the same equation scientists use to study stalactites in caves, but instead of water, stalactites are formed by the buildup of calcium left after the water evaporates.

“If we know the mechanisms by which stalactites form, well, we could better preserve our natural caves that we have here, and try to stop them from eroding,” Short says.

And now that scientists know how icicles are made, it could lead to breakthroughs to prevent them from forming on power lines and trees.

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Sharks Can Really Sniff out Their Prey,

and This Is How They Do It

Science (June 10, 2010) — It’s no secret that sharks have a keen sense of smell and a remarkable ability to follow their noses through the ocean, right to their next meal. Now, researchers reporting online on June 10th in Current Biology, have figured out how the sharks manage to keep themselves on course.

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It turns out that sharks can detect small delays, no more than half a second long, in the time that odors reach one nostril versus the other, the researchers report. When the animals experience such a lag, they will turn toward whichever side picked up the scent first.

“The narrow sub-second time window in which this bilateral detection causes the turn response corresponds well with the swimming speed and odor patch dispersal physics of our shark species,” known as Mustelus canis or the smooth dogfish, said Jayne Gardiner of the University of South Florida. All in all, it means that sharks pick up on a combination of directional cues, based on both odor and flow, to keep themselves oriented and ultimately find what they are looking for.

If a shark experiences no delay in scent detection or a delay that lasts too long — a full second or more — they are just as likely to make a left-hand turn as they are to make a right.

These results refute the popular notion that sharks and other animals follow scent trails based on differences in the concentration of odor molecules hitting one nostril versus the other. It seems that theory doesn’t hold water when one considers the physics of the problem.

“There is a very pervasive idea that animals use concentration to orient to odors,” Gardiner said. “Most creatures come equipped with two odor sensors — nostrils or antennae, for example — and it has long been believed that they compare the concentration at each sensor and then turn towards the side receiving the strongest signal. But when odors are dispersed by flowing air or water, this dispersal is incredibly chaotic.”

Indeed, Gardiner explained, recent studies have shown that concentrations of scent molecules could easily mislead. Using dyes that light up under laser light, scientists found that there can be sudden peaks in the concentrations of molecules even at a distance from their source.

Gardiner’s team suggests that the findings in the small shark species they studied may help to explain the evolution of the wide and flat heads that make hammerhead sharks so recognizable. One idea has held that the characteristic hammerhead may lend the animals a better sense of smell. But studies hadn’t shown their noses to be all that remarkable, really. For instance, they don’t respond to odors at concentrations lower than other sharks. The new findings suggest that the distance between their nostrils could be the key.

“If you consider an animal encountering an odor patch at a given angle, an animal with more widely spaced nostrils will have a greater time lag between the odor hitting the left and right nostrils than an animal with more closely spaced nostrils,” Gardiner said. “Hammerheads may be able to orient to patches at a smaller angle of attack, potentially giving them better olfactory capabilities than pointy-nosed sharks.” That’s a theory that now deserves further testing.

In addition to giving insights into the evolution and behavior of sharks, the findings might also lead to underwater robots that are better equipped to find the source of chemical leaks, like the oil spill that is now plaguing the Gulf Coast, according to the researchers.

“This discovery can be applied to underwater steering algorithms,” Gardiner said. “Previous robots were programmed to track odors by comparing odor concentrations, and they failed to function as well or as quickly as live animals. With this new steering algorithm, we may be able to improve the design of these odor-guided robots. With the oil spill in the Gulf of Mexico, the main oil slick is easily visible and the primary sources were easy to find, but there could be other, smaller sources of leaks that have yet to be discovered. An odor-guided robot would be an asset for these types of situations.”

The researchers include Jayne M. Gardiner, University of South Florida, Tampa, FL, Center for Shark Research, Mote Marine Laboratory, Sarasota, FL; and Jelle Atema, Boston University Marine Program, Boston, MA, Marine Biological Laboratory, Woods Hole, MA, Woods Hole Oceanographic Institution, Woods Hole, MA.

Sourced and published by Henry Sapiecha 11th June 2010

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Clam Cleanup

Biologists Clam Up Waterways

To Determine Sources Of Pollution

January 1, 2009 — Biologists are able to determine the sources of toxins in water by using clams as pollutant traps. Clams naturally clean water by feeding absorbing toxins in their tissues as they draw in water. By placing the clams downstream of industrial parks and highways, they can be analyzed for pollutants. Biologists open the clams after exposure to these waters and detach them from their shells– various lab tests reveal contaminants in the waterway.

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See also:
Plants & Animals

Many of our streams and rivers are contaminated with pollutants like pesticides, lead, arsenic and PCBs. It’s a problem that’s costly to clean up. Scientists are using a new, inexpensive way to fix the problem.

Lurking in many rivers and streams are contaminants. Some you can see, and some you can’t. Hidden chemicals ruin waterways and everything in it. To clean things up, biologists are teaming up with local high school students to dredge up clams to use as tiny detectives. They help by finding the source of toxic leaks.

“We’re using them as pollutant traps,” said Harriette Phelps, Ph.D., a biologist at the University of the District of Columbia in Washington, D.C.

Students put the clams in streams that lead to rivers. Clams then suck in water swept down from industrial parks and highways.

“It’s been a great experience to actually come and see them and be the ones to pick them up out of the water,” student Caitlin Virta said.

Clams clean the water as they feed, absorbing toxins in their tissues. The clams are collected back from streams. Then, scientists pry open the clams and detach them from their shell. Later, lab tests reveals the clam’s secret — the kinds and quantities of pollutants in the water.

“We can trace them back to sources, and then hopefully we can go from there and get rid of the sources,” Dr. Phelps said.

The clams detected a banned pesticide in Maryland, believed buried years ago and now slowly leaking. “I thought it was really cool how you could tell the health of a stream from analyzing clam leftovers,” Virta said.

It’s a cool way to clean up the environment.

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BIOACCUMULATION AND CLAMS: Clams are filter-feeders, meaning they draw water into their shells, remove the food they find, and then draw in more food-rich water to continue feeding. This means that lots of water works its way through their shells. The muscle of the clam gathers not only food, but other material suspended in water during this process, which can lead to the accumulation of toxins and pollutants. Bioaccumulation is the term for toxins and pollutants that collect in the tissue of an organism. Biomagnification is a related term, referring to the transfer of such substances from prey to predator. If a prey animal bioaccumulates toxins in its body, then its predator, after consuming many of the smaller animals will accumulate many, many times the amount of the toxin in any one of their prey.

SECONDARY STANDARDS: Even if your tap water meets the EPA’s basic requirement for safe drinking water, some people still object to the taste, smell or appearance of their water. These are aesthetic concerns, however, and therefore fall under the EPA’s voluntary secondary standards. Some tap water is drinkable, but may be temporarily clouded because of air bubbles, or have a chlorine taste. A bleach-like taste can be improved by letting the water stand exposed to the air for a while.

The American Geophysical Union contributed to the information

Sourced and published by Henry Sapiecha 7th June 2010

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SEX IN THE OCEAN IS GREAT FOR THESE OYSTERS

NEWLY INVENTED OYSTER BEDS ON WHICH OYSTERS GROW

BRING A NEW MEANING TO THE TERM ‘SEA BED’

Hi, this is Rex Ellis.

I am thrilled because my Harvest Post has now reached production stage! I have been developing this idea since 2006 and have had  great feed back and a lot of encouragement by the industry.
Have a look at the post with the baskets in the pic  and see for yourself. Today we have been out to sea and have sank the post within seconds into the sea bed. It was indeed very difficult to remove it again. The harvest post is very strong and can carry multiple baskets with single compartments in order to grow shellfish stress free and in a shorter time than so far possible thanks to 48 single compartments per basket.

I am ready to take your orders, please contact me for a quote on a custom made solution for your needs.

THE PRODUCT IS GUARANTEED TO HAVE A LIFE OF AT LEAST 25YEARS

…………………………………………………………………………………………………………………….

HARVEST POST INVENTOR

[OYSTER GROWING]

Rex Ellis

• Age: 62
• Gender: Male
• Astrological Sign: Libra
• Zodiac Year: Boar
• Industry: Technology
• Occupation: Inventor
• Location: Hervey Bay : Qld : Australia

About Me

I have worked in the plastic industry for over 20 years. We developed different products like tanks and a plastic picket fence with an inbuilt watering system. The idea about the revolutionising way of growing shellfish came to me when I saw how labour intensive and physically demanding the growing of shellfish is. Because I love eating oysters, scallops and mussels myself I want to see the highest quality of shellfish grown especially in New Zealand, my home country and Australia, my chosen place to live

0407 820 030
rexellisharvestpost@gmail.com

Sourced and published by Henry Sapiecha 4th May 2010

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Renewable Energy:

Inexpensive Metal Catalyst

Can Effectively Generate

Hydrogen from Water

Science (May 1, 2010) — Hydrogen would command a key role in future renewable energy technologies, experts agree, if a relatively cheap, efficient and carbon-neutral means of producing it can be developed. An important step towards this elusive goal has been taken by a team of researchers with the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Berkeley. The team has discovered an inexpensive metal catalyst that can effectively generate hydrogen gas from water.

“Our new proton reduction catalyst is based on a molybdenum-oxo metal complex that is about 70 times cheaper than platinum, today’s most widely used metal catalyst for splitting the water molecule,” said Hemamala Karunadasa, one of the co-discoverers of this complex. “In addition, our catalyst does not require organic additives, and can operate in neutral water, even if it is dirty, and can operate in sea water, the most abundant source of hydrogen on earth and a natural electrolyte. These qualities make our catalyst ideal for renewable energy and sustainable chemistry.”

Karunadasa holds joint appointments with Berkeley Lab’s Chemical Sciences Division and UC Berkeley’s Chemistry Department. She is the lead author of a paper describing this work that appears in the April 29, 2010 issue of the journal Nature, titled “A molecular molybdenum-oxo catalyst for generating hydrogen from water.” Co-authors of this paper were Christopher Chang and Jeffrey Long, who also hold joint appointments with Berkeley Lab and UC Berkeley. Chang, in addition, is also an investigator with the Howard Hughes Medical Institute (HHMI).

Hydrogen gas, whether combusted or used in fuel cells to generate electricity, emits only water vapor as an exhaust product, which is why this nation would already be rolling towards a hydrogen economy if only there were hydrogen wells to tap. However, hydrogen gas does not occur naturally and has to be produced. Most of the hydrogen gas in the United States today comes from natural gas, a fossil fuel. While inexpensive, this technique adds huge volumes of carbon emissions to the atmosphere. Hydrogen can also be produced through the electrolysis of water — using electricity to split molecules of water into molecules of hydrogen and oxygen. This is an environmentally clean and sustainable method of production — especially if the electricity is generated via a renewable technology such as solar or wind — but requires a water-splitting catalyst.

Nature has developed extremely efficient water-splitting enzymes — called hydrogenases — for use by plants during photosynthesis, however, these enzymes are highly unstable and easily deactivated when removed from their native environment. Human activities demand a stable metal catalyst that can operate under non-biological settings.

Metal catalysts are commercially available, but they are low valence precious metals whose high costs make their widespread use prohibitive. For example, platinum, the best of them, costs some $2,000 an ounce.

“The basic scientific challenge has been to create earth-abundant molecular systems that produce hydrogen from water with high catalytic activity and stability,” Chang says. “We believe our discovery of a molecular molybdenum-oxo catalyst for generating hydrogen from water without the use of additional acids or organic co-solvents establishes a new chemical paradigm for creating reduction catalysts that are highly active and robust in aqueous media.”

The molybdenum-oxo complex that Karunadasa, Chang and Long discovered is a high valence metal with the chemical name of (PY5Me2)Mo-oxo. In their studies, the research team found that this complex catalyzes the generation of hydrogen from neutral buffered water or even sea water with a turnover frequency of 2.4 moles of hydrogen per mole of catalyst per second.

Long says, “This metal-oxo complex represents a distinct molecular motif for reduction catalysis that has high activity and stability in water. We are now focused on modifying the PY5Me ligand portion of the complex and investigating other metal complexes based on similar ligand platforms to further facilitate electrical charge-driven as well as light-driven catalytic processes. Our particular emphasis is on chemistry relevant to sustainable energy cycles.”

This research was supported in part by the DOE Office of Science through Berkeley Lab’s Helios Solar Energy Research Center, and in part by a grant from the National science Foundation.

Sourced and published by Henry Sapiecha 2nd May 2010

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Microbes galore in seas; “spaghetti” mats Pacific

HUGE MATS OF TOXIC BACTERIA ON SEA BEDS

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By Alister Doyle, Environment CorrespondentPosted 2010/04/18 at 1:09 pm EDT

OSLO, Apr. 18, 2010 (Reuters) — The ocean depths are home to myriad species of microbes, mostly hard to see but including spaghetti-like bacteria that form whitish mats the size of Greece on the floor of the Pacific, scientists said on Sunday.

The survey, part of a 10-year Census of Marine Life, turned up hosts of unknown microbes, tiny zooplankton, crustaceans, worms, burrowers and larvae, some of them looking like extras in a science fiction movie and underpinning all life in the seas.

“In no other realm of ocean life has the magnitude of Census discovery been as extensive as in the world of microbes,” said Mitch Sogin of the Marine Biological Laboratory in Woods Hole, Massachusetts, head of the marine microbe census.

The census estimated there were a mind-boggling “nonillion” — or 1,000,000,000,000,000,000,000,000,000,000 (30 zeroes) — individual microbial cells in the oceans, weighing as much as 240 billion African elephants, the biggest land animal.

Getting a better idea of microbes, the “hidden majority” making up 50 to 90 percent of biomass in the seas, will give a benchmark for understanding future shifts in the oceans, perhaps linked to climate change or pollution.

Among the biggest masses of life on the planet are carpets on the seabed formed by giant multi-cellular bacteria that look like thin strands of spaghetti. They feed on hydrogen sulphide in oxygen-starved waters in a band off Peru and Chile.

“Fishermen sometimes can’t lift nets from the bottom because they have more bacteria than shrimp,” Victor Gallardo, vice chair of the Census Scientific Steering Committee, told Reuters. “We’ve measured them up to a kilo (2.2 lbs) per square meter.”

GHOSTLY MATS

The census said they carpeted an area the size of Greece — about 130,000 sq km (50,000 sq miles) or the size of the U.S. state of Alabama. Toxic to humans, the bacteria are food for shrimp or worms and so underpin rich Pacific fish stocks.

The bacteria had also been found in oxygen-poor waters off Panama, Ecuador, Namibia and Mexico as well as in “dead zones” under some salmon farms. They were similar to ecosystems on earth that thrived from 2.5 billion to 650 million years ago.

Overall in the oceans, up to a billion microbe species may await identification under the Census, an international 10-year project due for completion in October 2010.

Tiny life was found everywhere, including at thermal vents with temperatures at 150 Celsius (300F) or in rocks 1,626 meters (5,335 ft) below the sea floor. Many creatures lack names or are hard to pronounce like loriciferans, polychaetes or copepods.

One major finding was that rare microbes are often found in samples where they can be outnumbered 10,000 to one by more common species. Isolated microbes may be lying in wait for a change in conditions that could bring a population boom.

Ann Bucklin, head of the Census of Marine Zooplankton that include tiny transparent crustaceans or jellyfish, said the seas were barely studied even by the census.

“Seventy percent of the oceans are deeper than 1,000 meters,” Bucklin, of the University of Connecticut, told Reuters. “The deep layer is the source of the hidden diversity.”

Paul Snelgrove, of Memorial University in Canada, said one sample in the South Atlantic in an area the size of a small bathroom — 5.4 square meters — turned up 700 species of copepod, a type of crustacean, 99 percent of them unfamiliar.

Just finding Latin names for each find will be hard. Scientists had rejected the idea of raising funds by letting people pay to have a marine “bug” named after them.

Sourced and published by Henry Sapiecha 21st April 2010

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Viruses Harnessed to Split Water

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What is it?

Terminalia catappa is a species of tropical tree that grows in Asia. It is widely believed that placing the dried leaves of this tree in your aquarium (especially with Betta fish) causes the animals better health and therefore longer life.

Alternative Names

Indian Almond leaf, Ketapang, Wild Almond, Badamier, Java Almond, Amandier de Cayenne, Tropical Almond, Myrobalan, Malabar Almond, Singapore Almond, Ketapang, Huu Kwang, Sea Almond, Kobateishi, West Indian Almond, Umbrella Tree, Amandel Huu Kwang, Kottamba

Benefits

Unsubstantiated claims of a reduced presence of fungus, boosted immune system and helping skin problems in fish are also reported.

The leaves do contain several flavonoids (like kamferol or quercetin), several tannins (such as punicalin, punicalagin or tercatin), saponines and phytosterols. Due to this chemical richness, the leaves (and also the bark) have long been used in different traditional medicines for various purposes.

It is also thought that the large leaves (7-10″ long) contain agents for prevention of cancers (although they have no demonstrated anticarcinogenic properties) and antioxidant as well as anticlastogenic characteristics.

In fishkeeping the leaves are also used to lower the ph and heavy metals of the water. It has been utilized in this way by Betta Breeders in Thailand for many years. Hobbyists across the world also use them for conditioning the betta’s water for breeding and harding of the scales.

Studies of rotting plant material (see bogwood) have shown that the organic material releases minerals as beneficial fungi and bacteria decompose it. This provides food for infusoria which in turn shrimps and fry enjoy eating as a natural diet.

Does it work?

Scientific sources of the benefits of Indian almond leaves to humans are few and far between. Certainly chemical analysis of these leaves show a high degree of variety of chemicals. We can find no similar scientific studies on the benefits of this leaf in aquariums.

Perhaps similar benefits may also be seen if you were to use standard bogwood in your aquarium. Bogwood is well known at lowering pH and reduces the toxicity of metals. Which is an aid to lowering the presence of fungus and certain species of bacteria. The organic matter is also as a food source for catfish like Plecos and is a natural food for infusoria which invertebrates like shrimp and other small fish feed off.

The tannins and other chemicals which are dissolved in the water by the decomposition of organic material is called Blackwater. There are many companies selling Amazon and African blackwater bottles. So Indian almond leaves may simply be Asia’s equivalent.

Certainly aquatic animals evolved alongside trees growing next to them. Tree leaves falling in and decomposing will have released dozens of trace minerals that the animals will have naturally absorbed. In an aquarium these chemicals will be missing so it seems sensible to assume that adding these chemicals via blackwater or bogwood will potentially restore this imbalance. The trick is to obtain the same species of plants that grow in the wild animals locale.

Failing that, other plants like Green tea, Tree spinach, Dock leaves, Cranberrys, etc. are all well known for their health benefits. Oak leaves are often used in aquariums as an alternative.

Purchasing the leaves

The leaves are not generally sold commercially in aquarium shops, though there is one product we’ve came across – Bio-Leaf by Degen Discus. eBay and AquaBid often have sellers of these items. So we recommend you look there. The leaves are not expensive.

• The leaves should be evenly brown on both sides with no signs of fungus mould (light grey patches). Give the leaf a rinse in tap water to remove any possible lingering pesticides, etc. before you add it to an aquarium is a prudent move.

• Keep any unused leaves in an air and watertight container away from light and heat will ensure that any unused leaves will keep for at least 4-6 months.

Indian almond leaves and Betta fish

There appears to be word-of-mouth speculation of this leaf being used by far eastern aquarists for hundreds of years to harden the skin and increase the health of this fighting fish after bouts of fights.

Dosage

Assuming an average 6-10″ (15.2-25.4cm) long leaf, you use one quarter of this for every 4L (1.1 US G.) litres for Bettas or 1-2 leaves per 50L (13.2 US G.) for other species. Leave them in the tank for around 15 days in a filter bag or let them lie loose, they will sink after 2-3 days. Expect the water to tint slightly brown with the tannins.

• Remove any active carbon before adding them. Afterwards carbon may be used to remove the tannins but this may impact on their benefit.
• Sourced and published by Henry Sapiecha 5th Oct 2009
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Coupled Water Tower/Wind Turbine Controller
Andras Tanczos
Helsinki, Finland

A jointed water tower/wind turbine controller stores wind energy in the water towers of the drinking water network. At strong winds, the extra electrical energy generated by the wind turbine can be used to pump water into the water tower. When there is no wind, this energy can be released with a hydro-turbine, and the water goes back to the wells. The pump of the water tower and the hydro-turbine are used to control the water level in the reservoir. The electricity from the wind turbine is used for pumping the water or for supplying the electrical grid. The controller can also be installed on existing water towers and water tanks placed on top of buildings.

Sourced and published by Henry Sapiecha 8th Sept 2009

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Scientists create liquid lens on a chip

STATE COLLEGE, Pa. (UPI) — U.S. scientists say they’ve created tunable fluidic micro lenses that can focus light at will while remaining stationary and can be fabricated on a chip.

The Pennsylvania State University research engineers said such fluidic lenses can be used for many applications, such as counting cells, evaluating molecules or creating on-chip optical tweezers. The lenses might also provide imaging in medical devices, eliminating the necessity of moving the tip of a probe, they added.

The researchers, led by Assistant Professor Tony Jun Huang, said conventional, fixed focal length lenses can focus light at only one distance and the entire lens must move to focus on an object or to change the direction of the light. Fluidic lenses, however, can change focal length or direction in less than a second while remaining in the same place.

“We use water and a calcium chloride solution because they are readily available and safe and their optical properties have been well characterized,” said Huang.

The research that included graduate students Sz-Chin Lin, Michael Lapsley, Jinjie Shi, Bala Juluri and Xiaole Mao was reported in a recent issue of the journal Lab on a Chip.

Copyright 2009 by United Press International

Sourced and published by Henry Sapiecha 18th May 2009

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