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Monday, December 30, 2013

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How To Water - Wine - Milk - Beer Chemistry Demonstration

Chemistry demonstrations in which solutions appear to magically change color leave a lasting impression on students and help instill an interest in science. Here's a color change demo in which a solution seems to change from water to wine to milk to beer simply be being poured into the appropriate beverage glass.
Difficulty: Average
Time Required: Prepare the solutions in advance; demo time is up to you

 

Here's How:

  1. First, prepare the glassware, since this demonstration relies on the presence of chemicals added to the glasses before the 'water' is added.
  2. For the 'water' glass: Fill the glass about 3/4 full of distilled water. Add 20-25 ml of saturated sodium bicarbonate with 20% sodium carbonate solution. The solution should have a pH = 9.
  3. Place a few drops of phenolphthalein indicator in the bottom of the wine glass.
  4. Pour ~10 ml saturated barium chloride solution into the bottom of the milk glass.
  5. Place a very small number of crystals of sodium dichromate into the beer mug. Up to this point, the set-up can be performed in advance of the demonstration. Just prior to performing the demo, add 5 ml concentrated HCl to the beer mug.
  6. To perform the demonstration, simply pour the solution from the water glass into the wine glass. Pour the resulting solution into the milk glass. This solution is finally poured into the beer mug.

Tips:

  1. Use goggles, gloves, and proper safety precautions when making the solutions and handling the chemicals. In particular, use caution with the conc. HCl, which can cause a serious acid burn.
  2. Avoid accidents! If you are using real drinking glasses, please reserve this glassware solely for this demonstration and take care that the prepared glassware is kept away from children/pets/etc. As always, label your glassware, too.

What You Need

  • distilled water
  • saturated sodium bicarbonate; 20% sodium carbonate ph=9
  • phenolphthalein indicator
  • saturated barium chloride solution (aqueous)
  • crystals of sodium dichromate
  • concentrated hydrochloric acid
  • water glass
  • wine glass
  • milk glass
  • beer mug

Valentine's Day Science Projects

Find a science project that is perfect for Valentine's Day! You can perform a color change reaction, make a chemical "beating heart", prepare a special Valentine gift, and more.

Printable Periodic Table of the Elements

Print or Download the Periodic Table 
The Periodic Table of the Elements is one of your best tools for working chemistry problems and making predictions about the properties of the elements. The online periodic table is useful since clicking on a symbol gives detailed element facts that you can't get on a single printed sheet of paper. However, it's really nice to be able to print out the table and move it around on your work space or write on it. Here are a few printable periodic tables for you. Each table prints out perfectly on a single 8-1/2" by 11" or standard printer paper page. Please feel free to download these to your computer, print them, and use them as hand-outs.
This color periodic table has circle tiles containing each element's atomic number, symbol, name and atomic weight.

Make Glowing Water

There are a couple of ways you get science projects to glow in the dark. You can use glow-in-the-dark paint, which is phosphorescent and glows anywhere from a few minutes to a few hours. Glowing paint or powder tends not to be very soluble, so it is good for some projects and not others. Tonic water glows very brightly when exposed to black light and is great for edible projects. Fluorescent dye is another option for a bright effect under a black light. You can extract non-toxic fluorescent dye from a highlighter pen to make glowing water:

  1. Use a knife to (carefully) cut a highlighter pen in half. It's a pretty simple steak knife and cutting board procedure.
  2. Pull out the ink-soaked felt that is inside the pen.
  3. Soak the felt in a small quantity of water. I made a video of what to expect.
Once you have the dye you can add it to more water to make glowing fountains, grow certain types of glowing crystals, make glowing bubbles, and use it for many other water-based projects.

The Difference Between Fluorine and Fluoride

First off, yes, it's fluorine and fluoride and not flourine and flouride. The mis-spelling is common, but the 'u' comes before the 'o'. Fluorine is a chemical element. Its anion, F-, or any of the compounds containing the anion are termed fluorides. When you hear about fluoride in drinking water, it comes from adding a fluorine compound (usually sodium fluoride, sodium fluorosilicate, or fluorosilicic acid) to drinking water, which dissociates to release the F- ion.

China-Japan tensions: Who has the smartest approach?

Japanese Prime Minister Shinzo Abe's visit to a shrine honoring war criminals has aggravated tensions between Japan and China, prompting one expert to say Beijing is taking a 'smarter approach' to the strained relations between Asia's two biggest economies.
Tensions between the world's second and third largest economies have flared up in recent years following a territorial dispute over the East China Sea islands, which disrupted trade between the two nations. More recently, Beijing's introduction of an air defense zone has raised tensions further.
Abe's controversial visit to the Yasukuni shrine in Tokyo on Boxing Day provoked criticism from China, while the U.S. Embassy said it was "disappointed" with Japan's leadership.
"The leadership in China seems smarter on this one and more astute on this and recognizing what is going on more than Abe. Abe seems a little bit more wound up on this," said David Zweig, director of the center on China's Transnational Relations at the Hong Kong University of Science and Technology.
Zweig said the U.S. government's decision to criticize Abe gave China a chance to "calm down and step back."
(Watch This: China-Japan island dispute: Is it worrying?)
"So it seems the Chinese are being a bit smarter on this, Abe is out on a limb a little bit here and I think the Chinese see that. They are thinking if the Americans are going to criticize him, let him dangle in the wind, that'd be a good thing," he added.
A resurgence of political tensions could threaten a recovery in trade relations between the two countries at a time when export numbers are all the more important for Japan amidst its ambitious plan to drag the economy out of over a decade of deflation.
Japanese exports to China recovered strongly in the first half of the year, recording an annual decline of only 0.6 percent, up from a 10.8 percent decline last year. From July to November, exports have surged to 18 percent.
The strong recovery in exports has given Abenomics a boost, but the prime minister faces a number of hurdles in 2014, including the planned consumption tax hike in April and the expected reduction in household spending as consumer prices tick upwards, which could derail his good work.

On This Day in Science History - December 30 - Robert Boyle

December 30th marks the passing of Robert Boyle. Boyle was an Irish chemist who made a significant contribution away from the alchemical idea of Aristotle's four elements to the atomic model of elements. He argued elements consisted of 'corpuscles' (atoms) instead of the four traditional elements of earth, air, fire and water. He also proposed nature could be broken down and described as a set of simple mathematical laws.

He also worked extensively with gases, especially with low pressure or 'rarefied airs' and vacuums. He demonstrated that vacuum can exist in nature, sound cannot travel though it, and animals cannot live without air. These experiments led to Boyle's ideal gas law where a gas at constant temperature will have changes in pressure inversely proportional to changes in volume containing the gas.

Boyle was also one of the founding members of the Royal Society that formed from a group of science and mathematically inclined people who met on a weekly basis in London and Oxford. He was elected president of the Society in 1680, but turned them down because the oath of office disagreed with his religious principles.

Guaranteed Scholarship Information

These are guaranteed scholarship money.
Just calculate your GPA in this format:
(Your GPA (as on transcript)*4)/ (maximum GPA in your educational system.)
For example:
In the HSC, if someone got 4.8, his GPA in 4.0 scale will be:
(4.8*4)/5=3.84
As for listed scholarships, just see if your score is equal or higher than the required scores of certain
university.
For example, one student will get full tuition scholarship in University of Alabama with a SAT score
of 1400 or above and a GPA of 3.5 or above (if got admitted). An additional scholarship of 2500 is
available in the University of Alabama if the student gets enrolled in the engineering school and
graduated with a STEM major. For that go to the website. If you have question about such
procedure. Ask in the comment box. I will try to response as soon as I can (remember I am not a
current undergrad students. I am applying this year)
Thanks.
University of Alabama
Award: Full Tuition
Residual COA: $13,122/year
Out-of-State Requirements: 3.5 GPA, 32 ACT or 1400 SAT (CR+M) In-State
Requirements: 3.5 GPA, 30 ACT or 1330 SAT (CR+M)
Website
Award: Full Tuition + $2,500/year
Residual COA: $10,622/year
Requirements (Eng/CS Only): 3.5 GPA, ACT 30 or 1330 SAT (CR+M)

Website
University of Alabama-Huntsville
Award: $15,750/year
Residual COA: $15,050/year (OOS), $3,500/year (In-State) Requirements:
4.0 GPA, 34 ACT or 1490 SAT (CR+M)
Website
University of Alabama-Birmingham
Award: $15,000/year (Full tuition for up to 25 credits per year)
Residual COA: Depends on number of hours taken Requirements:
3.0 GPA, 28 ACT
Website
Troy University
Award: Full Ride (Tuition+Room+Board)
Residual COA: $4,470/year
Requirements: 3.7 GPA, 31 ACT or 1380 SAT (CR+M)
Award: Full Tuition
Residual COA: $10,821/year
Requirements: 3.5 GPA, 27 ACT or 1220 SAT (CR+M)
Website
Alabama State University
Award: Full Ride (Tuition/Room/Board/Books+1,200/year)
Residual COA: $2,544/year
Requirements: 3.76 GPA, 28 ACT or 1230 SAT (CR+M)
Website
University of Arkansas-Little Rock
Award: Full Tuition+ ($10,000/year + OOS Tuition Waiver)
Residual COA: $11,997/year
Requirements: 3.0 GPA, 30 ACT or 1330 SAT (CR+M) website
University of Arkansas at Monticello
Award: Full Ride (Tuition+Room+Board)
Residual COA: $4,400/year
Requirements: 3.0 GPA and Top 10% Rank, 30 ACT
Award: Full Tuition+Room
Residual COA: $7,120/year
Requirements: 3.0 GPA, 27 ACT
Award: Full Tuition
Residual COA: $9,040/year
Requirements: 3.0 GPA, 24 ACT Website
University of Central Arkansas
Award: Full Tuition ($13,000/year)
Residual COA: $8,280/year
Requirement: 3.25 GPA, 31 ACT or 2020 SAT (CR+M+W) website
Southern Arkansas University
Award: Full Tuition+ ($11K/year)
Residual COA: $8,266/year
Requirement: 30 ACT website
Florida A&M
Award (In-State): Full Ride
Residual COA: $4,342/year
Award (OOS): Full Tuition and Fees
Residual COA: $13,096/year
Requirement: 3.5 GPA, 1800 SAT (CR+M+W) or 27 ACT website
Indiana-Purdue Fort Wayne
Award: Full Tuition
Residual COA: $13,622/year
Requirement: 32 ACT (including writing) or 2100 SAT (CR+M+W) website
Northern Illinois University
Award: $23,500/year
Residual COA: $12,021/year (OOS), $3,128/year (In State) Requirements:
3.75 GPA or Top 5% Class Rank, 33 ACT
Website
Western Illinois University
Award: $10,000 + room
Residual COA: $9,420/year (OOS), $5,144/year (In State)
Requirements: 3.5 GPA, 32 ACT or 1420 SAT (CR+M) website
Morningside College
Award: Full Tuition
Residual COA: $9,820/year
Requirements: 3.9 GPA, 31 ACT
Louisiana Tech University
Award: Full Ride (tuition, fees, and on-campus regular dorm and meals for four years)
Residual COA: $5,229/year
Requirements: 3.0 GPA, 32 ACT or 1400 SAT (CR+M)
University of Louisiana-Monroe
Award: Full Ride
Residual COA: $2,889/year
Requirements: 3.0 GPA, 31 ACT or 1360 SAT (CR+M) website
Southeastern Louisiana University
Award: ~Full Tuition ($6,500-$7,000 + OOS tuition waiver)
Residual COA: $9,628/year
Requirements: 3.0 GPA, 30 ACT
Website
Coppin State University
Award: Full Ride
Residual COA: $4,085/year
Requirements: 3.2 GPA, 1820 SAT (CR+M+W)
Award: Full Tuition
Residual COA: $12,103/year
Requirements: 3.0 GPA, 1590 SAT (CR+M+W) website
University of Mississippi (Ole Miss)
Award (OOS): Approximately 90% Tuition (Currently $15K/year, may not increase to match future
tuition increases)
Residual COA: $17,010/year
Requirements: 3.0 GPA, 32 ACT/1400 SAT (CR+M)
Award (In State): Approximately 80% Tuition (Currently $5K/year, may not increase to match future
tuition increases)
Residual COA: $16,526/year
Requirements: 3.0 GPA, 32 ACT/1400 SAT (CR+M)
Website
Jackson State University
Award: Full Ride (Tuition, Room, Board, Fees, Books)
Residual COA: $3,300/year
Requirements: 3.5 GPA, 27 ACT
Award: Full Ride (Tuition, Room, Board)
Residual COA: $4,100/year
Requirements: 3.0 GPA, 25 ACT
Award: Full Tuition
Residual COA: $10,594/year
Requirements: 3.0 GPA, 22 ACT
Website
Southeast Missouri State University
Award: Full Ride (Tuition+Room+Board)
Residual COA: $3,895/year
Requirements: 3.9 GPA, 33 ACT or 1440 SAT (CR+M)
Award: Full Tuition
Residual COA: $11,610/year
Requirements: 3.6 GPA, 28 ACT or 1250 SAT (CR+M) website
Missouri State University
Award: $5,000 + OOS tuition waiver (=~85% of OOS tuition)
Residual COA: $12,580/year
Requirements: 3.9 GPA or top 10% class rank, 28 ACT or 1250 SAT (CR+M) or IB diploma website
Ohio University
Award (In State): Full Tuition
Residual COA: $13,407/year
Requirements: 3.0 GPA, 32 ACT or 1400 SAT (CR+M)
Award (OOS): $6,000 + In-State Tuition (=~85% of OOS Tuition)
Residual COA: $16,371/year
Requirements: 3.0 GPA, 32 ACT or 1400 SAT (CR+M) website
Wayne State College
Award: Full Tuition
Residual COA: $9,580/year
Requirement: 30 ACT website
North Carolina Central University
Award: Full Ride+ (Tuition and fees, room, board, books, $1000/year, internships and a laptop)
Residual COA: $1,175/year
Requirement: 3.5 GPA, 29 ACT or 1900 SAT (CR+M+W)
Website
Newberry College
Award: Full Ride (Tuition, Fees, Room, and Board)
Residual COA: $3,500/year
Requirement: 3.5 GPA, 32 ACT or 1400 SAT (CR+M)
Website
Winthrop University
Award: ~Full Tuition ($14,000/year in-state, $24,000/year OOS)
Residual COA: $11,564/year
Requirement: 4.0 GPA, 35 ACT or 1500 SAT (CR+M)
Website
Columbia College
Award: Full Tuition
Residual COA: $11,438/year
Requirement: 29 ACT or 1300 SAT (CR+M)
Lee University
Award: Full Tuition
Residual COA: $10,944/year
Requirements: 32 ACT or 1410 SAT (CR+M)
Website
Texas State University
Award: Full Tuition ($8,000/year + OOS tuition waiver)
Residual COA: $11,814/year
Requirements: Top 15% Rank or IB Diploma, 32 ACT or 1400 SAT (CR+M)
Website
Prairie View A&M University
Award: Full Ride (Tuition, Fees, Room, Books)
Residual COA: $5,324/year
Requirements: 3.5 GPA, 1760 SAT (CR+M+W) or 26 ACT (including W)
Award: Full Tuition+ ($9,200/year + OOS Tuition Waiver)
Residual COA: $9,526/year
Requirements: 3.25 GPA, 1650 SAT (CR+M+W) or 24 ACT (including W)
Website
Utah Valley University
Award: Full Tuition
Residual COA: $12,700/year
Requirements: 3.9 GPA, 1980 SAT (CR+M+W) or 30 ACT website

Saturday, December 28, 2013

Taking Care of Our Pets in Tough Economic Times

News of tough economic times is everywhere, every day. People are spending less on themselves and on their pets. What have you sacrificed in terms of pet food or pet care? See how others are coping, and learn some money-saving tips to use at the food store and the veterinary office.

. Ways to Save Money on Pet Care and Vet Bills

 Pets not only require our time and attention, they require our money, too. Food, vaccinations, and veterinary medical care all add up. In today's tough economy, people are rethinking their personal expenses and cutting the budget where they can. Here are some tips to keep your pet in good health while saving money.

2. Pet Supplies and Food: Save Money with eCoupons

My mom is a coupon clipper. I try to be, but inevitably lose the little paper coupon before I even get to the store. Internet coupons are different though. You can use then online with just a couple mouse-clicks or print them out on my printer. It must be that full size paper that I also use as my list, because I rarely lose these "online" coupons, and have saved quite a bit of money on pet food using them.

3. Pet Heath Insurance - Is It Worth It?

Insurance for pets has been available for 20-plus years, but for most pet owners, the concept of pet health insurance is still relatively new. The variety of coverage plans, while encouraging, are often viewed with confusion and even suspicion as far as actually reducing the costs of pet care. Here are some perspectives from the viewers of this site and their experiences with pet health insurance.

4. Compare Pet Health Insurance and Wellness Plans

This is a growing series interviews with pet health insurance companies. The interview consists of the same 10-questions. Each insurance company participant answers the same questions so viewers can directly compare what is available and what may be best for their pet and lifestyle.

5. Does Your Pet Have Health Insurance?

People are curious about pet health insurance, but cautious about signing up. Do you have pet insurance for your pet(s)? Vote in the poll and add in your experiences in the comments section.

6. My pet is sick, and I can't afford to go to the vet

To some people, it is obvious that if times are tough financially, it is not the best time to adopt or buy a pet. The old adage seems to be: if you can't afford a pet (or pets) don't have them! However, as most pet lovers know, it isn't always that simple. Here are some tips to prepare for emergencies and unexpected costs, as well as ideas for helping pay for emergencies when they do occur.

7. Vaccinating Pets at Home: A Good Idea?

In today's economy, everyone is looking for ways to save money whenever possible, which is completely understandable. As far as untrained pet owners giving vaccinations at home after reading a how-to pamphlet, you can probably bet that my answer to this question is a "no." Here's why.

8. Are Pets Too Expensive?

In today's tough economy, people are rethinking where they shop, what they eat, and what car they drive. What about our pets? Costs for pet health care, food and other supplies has risen just as human health care and food costs have. Do you think that pet's are too expensive? A luxury item? Cast your vote in the poll and add your thoughts in the comments section.

নোয়াখালীতে যুবলীগকর্মী গুলিবিদ্ধ

শেখ হাসিনার প্রতিশ্রুতি

Grow Bismuth Crystals

Are you looking for a gorgeous crystal to grow? Try bismuth crystals. Bismuth is a metal that forms interesting geometrical 'hopper' crystals that are rainbow-colored from the thin oxide layer that forms on them. You can get bismuth at a sporting goods store or you can order it online. The crystals only take a matter of seconds to grow, so give it a try!
Bismuth Crystal Materials
  • bismuth
  • 2 stainless steel measuring cups or aluminum cans that you have cut in half to make shallow bowls
  • a stovetop, hot plate, or propane torch
You have a few different options for obtaining bismuth. You can use non-lead fishing sinkers (for example, Eagle Claw makes non-lead sinkers using bismuth), you can use non-lead ammunition (the shot will say it is made from bismuth on the label), or you can buy bismuth metal. The quality of crystals you obtain depends in part on the purity of the metal, so make sure you are using bismuth and not an alloy.


Grow Bismuth Crystals
Bismuth has a low melting point (271°C or 520°F), so it is easy to melt over high cooking heating. You are going to grow the crystals by melting the bismuth in a metal 'dish' (which will have a higher melting point than the bismuth), separate the pure bismuth from its impurities, allow the bismuth to crystallize, and pour away the remaining liquid bismuth from the crystals before it freezes around the crystals. None of this is difficult, but it takes some practice to get the cooling time just right. Don't worry -- if your bismuth freezes you can remelt it and try again. Here are the steps in detail:
  • Place the bismuth in one of your metal 'dishes' and heat it over high heat until it melts. It's a good idea to wear gloves since you are producing a molten metal, which is not going to do you any favors if it splashes onto your skin. You'll see a skin on the surface of the bismuth, which is normal.
  • Preheat the other metal container. Carefully pour the melted bismuth into the heated clean container. You want to pour the clean bismuth out from under the gray skin, which contains impurities which would negatively affect your crystals.
  • Set the clean bismuth in its new container on a heat-insulated surface. The cooling rate of the bismuth affects the size and structure of the resulting crystals, so you can play with this factor. Generally, slower cooling produces larger crystals. You do not want to cool the bismuth until it is solid!
  • When the bismuth has started to solidify, you want to pour the remaining liquid bismuth away from the solid crystals. This happens after about 30 seconds of cooling. You can tell it is about the right time to pour the liquid away from your crystals when the bismuth is set, but has just a little jiggle to it when jarred. Sounds scientific, right?
  • Once the crystals have cooled, you can snap them out of the metal container. If you are not satisfied with the appearance of your crystals, remelt and cool the metal until it is just right.
If you try this project and would like to share your tips and tricks, please feel free to post a reply.

Colored Flame Spray Bottles

Colored flame spray bottles are one of the easiest and most memorable chemistry demonstrations you can perform! The demo also makes a great chemistry "magic" trick, although of course it is based on the emission spectra seen in flame tests. Chemist Mitch at the Museum of Science and Industry in Chicago shows how to perform this demonstration safely and effectively:.
    • Wear protective clothing. Lab coats look cool, plus they protect your clothes. You can't see this, but Mitch is wearing long pants and shoes that cover his feet.
    • Wear your safety goggles. Modern safety goggles are comfortable, fashionable and safe.
    • Direct the spray away from the audience. When the alcohol hits the flame, it produces a fairly dramatic plume of flame. You don't need to scare anyone or ignite any hair.
    • If you have one, use a clear blast shield. In this demonstration, droplets of liquid can splash harmlessly on the inside of the shield, controlling the flame.
    • Have fun with it! Excitement about science is contagious.
    • Explain the chemistry behind the demonstration. This hot pink color comes from lithium. Hot pink is the perfect color for a cool fire demonstration. Of course, you can make any color of the rainbow

On This Day in Science History - December 29 - Charles Goodyear

December 29th is the birthday of the man who discovered the process to vulcanize rubber. Charles Goodyear spent several years trying to find a method to convert rubber into a substance that would not turn brittle in the cold or turn to goo in the heat. His early attempts found rubber that would rot after time or still turn sticky in heat. He ultimately found the answer by accident. He spilled a mixture of rubber mixed with sulfur on a hot stove and cured the rubber into a solid mass.

After he patented his process, he started a small company to find uses for his rubber. Unfortunately, he spent most of his efforts on defending his patents and in lawsuits and his business failed. The Goodyear Tire and Rubber Company had nothing to do with Charles Goodyear and was formed 38 years after his death in 1860.

Tuesday, December 17, 2013

Molecules Formed by Covalent Bonds

For example, the oxygen molecule consists of two atoms of oxygen. In the case of oxygen, the bond that holds the two atoms together is known as a covalent bond, and here is how it works.

The oxygen atom has 8 each of protons, neutrons, and electrons. The protons and neutrons are found in the center of the atom, known as the nucleus, and the electrons surround the nucleus in layers, or shells. The oxygen atom has 2 electrons in its first shell, and 6 in its second and outer shell. However, in chemistry, there exists the octet rule, which states that atoms generally strive to have 8 electrons in their outer shell. The oxygen therefore is 2 electrons away from a complete outer shell. When it binds with another oxygen atom, they can share two pairs of electrons and so each will have 8. When atoms share electrons like that, they form a molecule through a covalent bond.

Molecules Formed by Ionic Bonds

Molecules can also be formed through other kinds of chemical bonds, for example, an ionic bond. An example this is sodium chloride, or table salt. In an ionic bond, one atom has a much greater ability to attract electrons than the other atom. In this case, the chlorine, which is only 1 electron short of a complete outer shell, will steal that electron from the sodium, which has only 1 outermost electron. This turns the sodium into a positively charged ion, and the chlorine into a negatively charged ion, and the two atoms end up being held together by an electrostatic charge.

Meaning of a Mole

Now what is a mole? A mole is simply a counting number, much like a dozen. When we say "dozen", we mean 12; well, when we say "a mole" we mean 6.022 x 10 to the 23. Moles make it easier to quantify chemical substances. The periodic table lists the weights of all the elements in grams per mole.

Examples of Finding Molar Mass

For example, oxygen has molar mass of 16, which means 6.022 x 10 to the 23 atoms of oxygen weigh 16 grams. Hydrogen has a molar mass of 1. To find out the molar mass of a molecule, such as water, we need to add up the molar masses of the atoms it is composed of. Since water has two atoms of hydrogen and 1 atom of oxygen, its molar mass is 18 grams per mole.

On This Day in Science History -- December 17 -- Carbon 14 Dating

December 17th is Willard Libby's birthday. Libby was the American physical chemist who developed the carbon-14 dating technique. This method is used to determine the age of 'once living' objects up to approximately 50,000 years.

Carbon 14 is an isotope of carbon that is created naturally in the atmosphere by cosmic rays which in turn is breathed by living things or absorbed by plants. Over a lifetime of breathing, plants and animals maintain a natural ratio of carbon-14 to carbon-12. When the living thing dies, it stops absorbing the carbon-14 from the air.
                                                              147N + 10n → 146C + 11H
Carbon-14 decays into nitrogen by beta decay over time, but the process takes a long time. The half life of carbon-14 is 5,720 years, meaning after 5,720 years, the organism will have half the carbon-14 levels it did when it was alive. If you measure the amount of carbon-14 in a once living object, you can determine the approximate age of the organism.

Find out what else occurred on this day in science history.

Can we turn unwanted carbon dioxide into electricity?

Researchers are developing a new kind of geothermal power plant that will lock away unwanted carbon dioxide (CO2) underground -- and use it as a tool to boost electric power generation by at least 10 times compared to existing geothermal energy approaches.
The technology to implement this design already exists in different industries, so the researchers are optimistic that their new approach could expand the use of geothermal energy in the U.S. far beyond the handful of states that can take advantage of it now.
At the American Geophysical Union meeting on Friday, Dec. 13, the research team debuted an expanded version of the design, along with a computer animated movie that merges advances in science with design and cognitive learning techniques to explain the role that energy technologies can have in addressing Climate-Change'>climate change.

The new power plant design resembles a cross between a typical geothermal power plant and the Large Hadron Collider: It features a series of concentric rings of horizontal wells deep underground. Inside those rings, CO2, nitrogen and water circulate separately to draw heat from below ground up to the surface, where the heat can be used to turn turbines and generate electricity.
The design contrasts with conventional geothermal plants, explained study co-author Jeffrey Bielicki, assistant professor of energy policy in the Department of Civil, Environmental and Geodetic Engineering and the John Glenn School of Public Affairs at The Ohio State University.
"Typical geothermal power plants tap into hot water that is deep under ground, pull the heat off the hot water, use that heat to generate electricity, and then return the cooler water back to the deep subsurface. Here the water is partly replaced with CO2 or another fluid -- or a combination of fluids," he said.
CO2 extracts heat more efficiently than water, he added.
This approach -- using concentric rings that circulate multiple fluids -- builds upon the idea to use CO2 originally developed by Martin Saar and others at the University of Minnesota, and can be at least twice as efficient as conventional geothermal approaches, according to computer simulations.
"When we began to develop the idea to use CO2 to produce geothermal energy, we wanted to find a way to make CO2 storage cost-effective while expanding the use of geothermal energy," said Jimmy Randolph, postdoctoral researcher in the Department of Earth Sciences at the University of Minnesota.
"We hope that we can expand the reach of geothermal energy in the United States to include most states west of the Mississippi River," Bielicki said.
The current research team includes Ohio State, the University of Minnesota and Lawrence Livermore National Laboratory, where geoscientist Tom Buscheck came up with the idea to add nitrogen to the mix.
He and his colleagues believe that the resulting multifluid design will enable geothermal power plants to store energy away -- perhaps hundreds of gigawatt hours -- for days or even months, so that it is available when the electricity grid needs it. The underground geothermal formation could store hot, pressurized CO2 and nitrogen, and release the heat to the surface power plant when electricity demand is greatest. The plant could also suspend heat extraction from the subsurface during times of low power demand, or when there is already a surplus of renewable power on the grid.
"What makes this concept transformational is that we can deliver renewable energy to customers when it is needed, rather than when the wind happens to be blowing, or when spring thaw causes the greatest runoff," Buscheck said.
In computer simulations, a 10-mile-wide system of concentric rings of horizontal wells situated about three miles below ground produced as much as half a gigawatt of electrical power -- an amount comparable to a medium-sized coal-fired power plant -- and more than 10 times bigger than the 38 megawatts produced by the average geothermal plant in the United States.
The simulations also revealed that a plant of this design might sequester as much as 15 million tons of CO2 per year, which is roughly equivalent to the amount produced by three medium-sized coal-fired power plants in that time.
Bielicki noted the possibility of expanding the use of geothermal energy around the country. Right now, most geothermal power plants are in California and Nevada, where very hot water is relatively close to the surface. But the new design is so much more efficient at both storing energy and extracting heat that even smaller-scale "hotspots" throughout the western U.S. could generate power.
The eastern U.S. is mostly devoid of even small hotspots, so geothermal power would still be limited to a few particularly active areas such as West Virginia, he said.
Another caveat: The geothermal plant would probably have to be connected to a large CO2 source, such as a coal-fired power plant that is scrubbing the CO2 from its own emissions. That connection would likely be made by pipeline.
Buscheck added, however, that the study showed that this design could work effectively with or without CO2, and said a pilot plant based on this design could initially be powered solely by nitrogen injection to prove the economic viability of using CO2. The research team is currently working on more detailed computer model simulations and economic analyses for specific geologic settings in the U.S.
The project is unusual in part because, as they were refining their ideas, the engineers joined with Shannon Gilley, then a master of fine arts student at the Minneapolis College of Art and Design. Bielicki worked with Gilley for more than a year to create the computer animated video titled "Geothermal Energy: Enhancing our Future." Part of Gilley's task was to communicate the more complex details of Climate-Change'>climate change, CO2 storage and geothermal energy to the general public.
"We built this concept of public outreach into our efforts not just to communicate our work, but also to explore new ways for scientists, engineers, economists and artists to work together," Bielicki said.
Co-authors on the presentation also included Mingjie Chen, Yue Hao and Yunwei Sun, all of Lawrence Livermore National Laboratory. Work at the University of Minnesota and Ohio State has been funded by the National Science Foundation, while work at Lawrence Livermore National Laboratory has been funded by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy.
Heat Mining Co. LLC, a startup company spun off from the University of Minnesota, expects to have an operational project, based on an earlier form of the approach, in 2016.

Nitrogen deposition poses threat to diversity of Europe's forest vegetation

Unless nitrogen emissions are curbed, the diversity of plant communities in Europe's forests will decrease. Atmospheric nitrogen deposition has already changed the number and richness of forest floor vegetation species in European forests over the last 20-30 years. In particular, the coverage of plant species adapted to nutrient-poor conditions has reduced. However, levels of nitrogen deposition in Finnish forests remain small compared to Southern and Central Europe.
These results will be presented as part of international research published in the journal Global Change Biology. Researchers from the Finnish Environment Institute and the Finnish Forest Research Institute (Metla) participated in this research, which concludes that unless nitrogen emissions are curbed, the diversity of plant communities in Europe's forests will decrease. The work involved the examination of long-term changes in vascular plant communities within a 1 300 monitoring grid covering 28 forested areas in various parts of Europe.
The number and richness of forest floor vegetation species in European forests have changed over the last 20 to 30 years, due to wet and dry deposition of atmospheric nitrogen. In particular, low-nutrient or acidic habitats are sensitive to long-term nitrogen deposition. Among such habitats, coverage of species such as heather and may lily has been reduced in many areas, in which nitrogen deposition has exceeded a certain threshold value i.e. the critical nitrogen load.
The largest changes in vegetation have occurred in Southern and Central European forests. Although deposition has not yet markedly affected species numbers within plant communities, most new species spreading into forests during the monitoring period have been types that favour nitrogen.
Finland still has a small nitrogen load
Four monitoring areas located in Finnish nature reserves were covered by the research. These areas were subject to markedly lower nitrogen deposition (0.6-1.9 kg of nitrogen per hectare per year) compared to areas subject to greater nitrogen deposition in Central Europe (10-20 kg N/ha/year) or Italy (20-30 kg N/ha/year).
Critical nitrogen loads applied in the research are based on the previously published results of long-term field research and experiments. By critical nitrogen loads, we refer to nitrogen deposition known to have harmful effects on the functions of more sensitive organisms in the ecosystem. The critical nitrogen load in boreal forests is estimated to be fairly small (5-8 kg N/ha/y), since northern forest ecosystems are highly sensitive to the effects of excess nitrogen. Such areas in Finland include nutrient-poor and dry pine forests in particular.
Although nitrogen deposition remains small in Northern Europe, even a slight rise in long-term deposition could change the competitive relationship of vascular plants by promoting the dissemination and growth of nitrogen-favouring species.
The effects of nitrogen deposition on Finland's forest vegetation can only be investigated with the assistance of a permanent environmental monitoring network. According to long-term monitoring by the Finnish Forest Research Institute (Metla), tree felling is still the key factor in changes to forest floor vegetation.
This monitoring reveals a reduction in lichens throughout Finland, including in unfelled forests. In Northern Finland, reindeer grazing is the key factor in lichen reduction. Slow-growing lichens in Southern Finland can also suffer due to the rapid growth of and shading by plants benefiting from nitrogen deposition.

FDA issues proposed rule to determine safety and effectiveness of antibacterial soaps

The U.S. Food and Drug Administration today issued a proposed rule to require manufacturers of antibacterial hand soaps and body washes to demonstrate that their products are safe for long-term daily use and more effective than plain soap and water in preventing illness and the spread of certain infections. Under the proposal, if companies do not demonstrate such safety and effectiveness, these products would need to be reformulated or relabeled to remain on the market.
Today’s action is part of a larger, ongoing review of antibacterial active ingredients by the FDA to ensure these ingredients are proven to be safe and effective. This proposed rule does not affect hand sanitizers, wipes, or antibacterial products used in health care settings.
Millions of Americans use antibacterial hand soap and body wash products. Although consumers generally view these products as effective tools to help prevent the spread of germs, there is currently no evidence that they are any more effective at preventing illness than washing with plain soap and water. Further, some data suggest that long-term exposure to certain active ingredients used in antibacterial products—for example, triclosan (liquid soaps) and triclocarban (bar soaps)—could pose health risks, such as bacterial resistance or hormonal effects.
“Antibacterial soaps and body washes are used widely and frequently by consumers in everyday home, work, school, and public settings, where the risk of infection is relatively low,” said Janet Woodcock, M.D., director of the FDA’s Center for Drug Evaluation and Research (CDER). “Due to consumers’ extensive exposure to the ingredients in antibacterial soaps, we believe there should be a clearly demonstrated benefit from using antibacterial soap to balance any potential risk.”
The widespread consumer use of antibacterial products, the accumulated scientific information and concerns raised by health care and consumer groups have prompted the FDA to reevaluate what data are needed to classify the active ingredients in consumer antibacterial products as “generally recognized as safe and effective” or GRASE.  Under the proposed rule, manufacturers who want to continue marketing antibacterial products will be required to provide the agency with additional data on the products’ safety and effectiveness, including data from clinical studies to demonstrate that these products are superior to non-antibacterial soaps in preventing human illness or reducing infection.
“While the FDA continues to collect additional information on antibacterial hand soaps and body washes, we encourage consumers to make an educated choice about what products they choose to use,” said Sandra Kweder, M.D., deputy director, Office of New Drugs at CDER. “Washing with plain soap and running water is one of the most important steps consumers can take to avoid getting sick and to prevent spreading germs to others.”
Consumers should continue to be diligent about washing their hands. If soap and water are not available, an alcohol-based hand sanitizer that contains at least 60 percent alcohol should be used.  More information on appropriate hand washing from the CDC may be found here.
Almost all soaps labeled “antibacterial” or “antimicrobial” contain at least one of the antibacterial ingredients addressed in the proposed rule. The most common active ingredients in antibacterial soaps are triclosan and triclocarban. Some soaps labeled “deodorant” may also contain these ingredients.
The proposed rule does not require the antibacterial soap products to be removed from the market at this time. When the proposed rule is finalized, as previously stated, either companies will have provided data to support an antibacterial claim, or if not, they will have to reformulate (remove antibacterial active ingredients) or relabel (remove the antibacterial claim from the product’s labeling) these products in order to continue marketing. The proposed rule is available for public comment for 180 days, with a concurrent one year period for companies to submit new data and information, followed by a 60-day rebuttal comment period.
Source: FDA

Monday, December 16, 2013

‘শপথ এবার প্রতিরোধের’

লাখো কণ্ঠে ‘আমার সোনার বাংলা’

বেয়াল্লিশ বছর আগে যে মুহূর্তে যে স্থানটিতে বাঙালির মুক্তির সনদ লেখা হয়েছিল, মুক্তিযুদ্ধে বিজয়ের সেই ক্ষণে সেই স্বাধীনতার উদ্যানেই লাখো কণ্ঠ গাইল ‘আমার সোনার বাংলা, আমি তোমায় ভালোবাসি’।

রবীন্দ্রনাথ ঠাকুরের এই গানটিই একাত্তরের রণাঙ্গনে বাঙালি জাতিকে প্রেরণা যুগিয়েছিল, যা পরে বাংলাদেশের জাতীয় সংগীত হিসাবে গ্রহণ করা হয়।
সোহরাওয়ার্দী উদ্যানে স্থাপিত ‘বিজয় ২০১৩’র মঞ্চে সোমবার বিকাল ৪টা ৩১মিনিটে এই গানে কণ্ঠ মেলান উপস্থিত জনতা।
এবার সম্মিলিতভাবে এই উত্সব পালন করছে বিজয় ২০১৩ উদযাপন জাতীয় কমিটি, গণজাগরণ মঞ্চ, সেক্টর কমান্ডার্স ফোরাম, মুক্তিযুদ্ধ চেতনা বাস্তবায়ন কমিটি এবং বিজয় ৪:৩১ মঞ্চ।

জাতীয় সংগীত পরিবেশনের আগে স্বাধীন বাংলা বেতার কেন্দ্রের শিল্পীরা পরিবেশন করেন একাত্তরে মুক্তিকামী মানুষকে শক্তি যোগানো বিভিন্ন গান। পরে তারাও সমবেত কণ্ঠের জাতীয় সংগীতে অংশ নেন।
১৯৭১ সালের ১৬ ডিসেম্বর বিকাল ৪টা ৩১ মিনিটে পাকিস্তানি বাহিনী এই উদ্যানেই আত্মসমর্পণের দলিলে সই করেছিল, তখন এর নাম ছিল রেসকোর্স ময়দান।মুক্তিযুদ্ধের উপ অধিনায়ক অবসরপ্রাপ্ত এয়ার ভাইস মার্শাল একে খন্দকার বীর উত্তম বলেন, “সেই ক্ষণে জাতীয়ভাবে আমাদের প্রাণের জাতীয় সংগীতকে কোটি কণ্ঠে পরিবেশনাই আজকের অনুষ্ঠানের মূল প্রতিপাদ্য।”

World's largest human flag !

Bangladesh attempts to create the world's largest 'human flag'





This Day in Science History -- December 16 -- Johann Ritter

December 16th is Johann Wilhelm Ritter's birthday. Ritter was a German scientist who invented one of the first dry pile galvanic batteries. Early batteries used electrodes dipped in an acid solution where the energy is produced through oxidation reactions. A dry pile uses just enough moisture to function and did not have the dangers of spilling acid solutions. Ritter's pile used alternating pieces of silver and zinc foil separated by pieces of paper.

Ritter was also responsible for the discovery of the ultraviolet region of the electromagnetic spectrum. While investigating the discoloration of silver salt crystals exposed to sunlight, he discovered there was a part of sunlight beyond the violet range responsible for the discoloration. He initially called this part of the light spectrum 'de-oxidizing rays' because of their chemical reactivity.

Find out more about electrochemical cells, redox reactions and what else occurred on this day in science history.

Introduction to Chemistry

What Is Chemistry?Chemistry is the study of matter and energy and the interactions between them. This is also the definition for physics, by the way. Chemistry and physics are specializations of physical science. Chemistry tends to focus on the properties of substances and the interactions between different types of matter, particularly reactions that involve electrons. Physics tends to focus more on the nuclear part of the atom, as well as the subatomic realm. Really, they are two sides of the same coin.

Why Study Chemistry?
Because understanding chemistry helps you to understand the world around you. Cooking is chemistry. Everything you can touch or taste or smell is a chemical. When you study chemistry, you come to understand a bit about how things work. Chemistry isn't secret knowledge, useless to anyone but a scientist. It's the explanation for everyday things, like why laundry detergent works better in hot water or how baking soda works or why not all pain relievers work equally well on a headache. If you know some chemistry, you can make educated choices about everyday products that you use.

What Fields of Study Use Chemistry?
You could use chemistry in most fields, but it's commonly seen in the sciences and in medicine. Chemists, physicists, biologists, and engineers study chemistry. Doctors, nurses, dentists, pharmacists, physical therapists, and veterinarians all take chemistry courses. Science teachers study chemistry. Fire fighters and people who make fireworks learn about chemistry. So do truck drivers, plumbers, artists, hairdressers, chefs... the list is extensive.
What Do Chemists Do?
Whatever they want. Some chemists wor
k in a lab, in a research environment, asking questions and testing hypotheses with experiments. Other chemists may work on a computer developing theories or models or predicting reactions. Some chemists do field work. Others contribute advice on chemistry for projects. Some chemists write. Some chemists teach. The career options are extensive.

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