Kalle Levon, Polytechnic University, <>, “Macromolecular Chemistry for Safe and Sustainable World.”

          The presentation discussed the important role of macromolecular chemistry for the development of sensors and sensor networks for security and for the preparation of tools for health diagnostics.

           This month Professor Kalle Levon, Polytechnic University, spoke about his work with conductive polymers and the current direction of the scientific world market. Right now, we are moving towards energy, environment and health. There is a strong push to conserve and find new sources of reusable energy as well as to preserve our environment for future generations. The demand for preventive medical care has also led to a movement towards developments in diagnostic technology and earlier detection techniques. Ongoing research in information technology, biotechnology and nanotechnology are aiding the developments in these fields by providing scientists with the necessary up-to-date tools. These areas enjoy a substantial amount of federal funding, a good indicator of future employment opportunities.
          With the increase in energy consumption, alternative energy sources have become a hot topic. Currently, most of our energy comes from petroleum 40%, coal 23.3%, natural gas 22.5%, hydroelectric 7.2%, and nuclear energy 6.6%. The alternative energy movement focuses on replacing the top three energy sources, which produce millions of tons of carbon dioxide and other harmful byproducts, with cleaner, renewable energy sources such as solar and wind energy. Japan has invested enormously in solar energy while scientists are researching to harness wind energy on the nanoscale. The interest in these alternate energy sources is in response to the significant climate changes from the 1800s to 2000 and is an effort to protect the environment by preventing further global warming and ice sheet melting.
         Professor Levon believes it is important to focus on the changes that are happening around us. The change in climate foreshadow a major environmental problem. Many other events can also be predicted and detected earlier by looking at changes that occur. The use of biomarkers, algorithms and decision noise to detect symptoms and monitor changes can help predict events, like being predisposed to cancer, and lead to earlier and earlier detection so treatment can be initiated sooner with higher chances of success.
          Professor Levon is a leading researcher in the areas of phase separation in polymer blends and solutions, gelation and conductive polymers. According to the theory of percolation, increasing the connectivity of particles and polymers can lead to conductivity when things are above the percolation threshold. Using this theory, organic conducting polymers have been developed which can become as conductive as metals when activated.
        So far, these electrically and ionically conductive polymers have been used as the conductive component in sensors, diagnostics, and paper and temperature indicators. The electro-active materials can be deposited by ink-jet, gravure, or flexo-printing techniques to make thin, flexible film batteries and organic light emitting diodes which are more energy efficient. The conductive polymers can also be applied to create fast swipe credit cards and print newspapers ads that give off radiation that can be picked up by devices, like cell phones, which would decode the radiation and transfer detailed information about the product onto the phone. Also, this technology of creating organic conductive polymers can be used to make conjugate polymers like DNA: First, one polymer is made electrically negative so that it would attach to a positively charged surface. Then, a positively charged polymer is introduced and it is allowed to hybridize and form ionic bonds with the first polymer under the guidance of electrodes. Additional layers can also be added on using the same process.
       Currently, Professor Levon is exploring the burgeoning field of linking computers and biotechnology to find a way to use these biological polymers to detect specific particles quickly and efficiently, like anthrax spores in the air. He aims to create small chips with 500 wells, each containing a matrix of polymers with different binding properties. The polymers would become conductive and pass electrical impulses once they form bonds with the particles in the air. The information on the different characteristics present would then be sent to be processed by a computer which would search through its extensive database to identify the particle by finding a matching combination of traits.
       Professor Levon has already conducted successful experiments in which he used this principle to detect and identify Bacillus bacterial spores. Using synthetic ligands as the conductive polymer because they were stable, selective, convenient and allowed for continuous monitoring, Professor Levon was able to determine the combination of traits that specifically identifies one species of Bacillus and not others.  With further research, devices like the chips Professor Levon is developing could be placed throughout the world to detect the presence and movement of gases, toxic compounds, small molecular biomarkers, pathogens and pesticides. They would also play an important role on the battlefield, particularly in biological warfare, to quickly detect the presence of pathogens in the air and toxic fumes. Therefore, with federal funding and the military need for fast and wide-ranged detectors and particle identifiers, there are unlimited opportunities in this field of biotechnology.

Dominic Vellucci, Principal Scientist, Kraft Foods Research, Tarrytown, NY, , “How Sweet It Is.” The search for natural sweeteners.

        Joe Sencen started the meeting with two demonstrations. He half filled a “ziplock” platic bag with water and then pierced it with several very sharp pencils (a la balloon and knitting needle) to show that long chain polymers have room to “spread.”  Next, he did a filtration analog. He made a cone from open mesh plastic sheeting, supported it in a beaker and pour in a mixture of small and large beads. The large beads were retained in the cone after the small ones were helped through the “filter” by shaking.
        This month Dominic Vellucci, a Principle Scientist at Kraft Foods Research, Westchester County, spoke about the sweeteners available today and their applications in the food industry. The current arsenal of sweeteners developed for the food industry and the public includes: natural and caloric carbohydrate sweeteners, bulk sweeteners, natural high intensity sweeteners, and artificial high intensity sweeteners. Their use is dependent on their taste, color, solubility, stability (temperature and pH), caloric value and cost-effectiveness.
The sweeteners are also characterized by their sweetness intensity curve which graphs the sweeteners’ sweetness in relation to time. This curve shows the maximum intensity of the sweetener, how fast it reaches its peak intensity, and the duration of the sweetness. For example, Acesulfame K (Ace-K) has an early onset of sweetness while aspartame has a later onset and a lingering aftertaste. Sugar, or sucrose, is the “gold standard” for sweeteners and others are judged relative to it. So, in order to achieve a sweetness profile that is similar to sucrose, sweeteners are often blended to synergize their qualities and smooth out the sweetness intensity curve.
        The traditional sweeteners are the carbohydrate sweeteners which provide four kcal per gram. These include sucrose, glucose, fructose, corn syrup, high fructose corn syrup, honey and molasses. Sucrose, derived from sugar canes and beets, has a relative sweetness of 1 and provides functionality in addition to sweetness with its unique texture and its ability to function as a moisture controller in food products. Glucose (dextrose) is derived from the complete hydrolysis of corn starch and is 0.8 times as sweet as sucrose. Since it is a reducing sugar, it also aids in the browning process in bakery applications. Fructose, or fruit sugar, is the sweetest of the carbohydrate sweeteners with sweetness 1.2-1.7 times that of sucrose. It can be obtained from the complete hydrolysis of corn starch followed by enzymatic conversion of glucose to fructose, or from the inversion of sucrose and the hydrolysis of fructan polymers (inulin). Fructose is also effective in moisture control and is sometimes used synergistically with sucrose to reduce the total amount of sweetener needed.
        Corn syrups are derived by the incomplete hydrolysis of corn starch, and their functionality depends on the dextrose equivalent (DE), which indicates the degree to which the starch is hydrolyzed. High fructose corn syrup (HFCS) is a high DE corn syrup that is isomerized to form fructose. At equilibrium, this process produces a 42% fructose corn syrup which is 90% as sweet as sucrose. The 42% high fructose corn syrup is the most commonly used HFCS since it is the cheapest. However, 55% HFCS, which is as sweet as sucrose, is used in carbonated drinks like Coke and Pepsi. Ninety percent HFCS is also available but it is rarely used due to the higher costs. Besides their use in carbonated drinks, corn syrups are also widely used in the food industries as primary sweeteners for their flavor, texture and the ability to control sweetness and moisture and inhibit crystallization. (There have been health concerns over the increasing consumption of fructose from high fructose corn syrups in processed foods because fructose has been shown to increase blood lipid levels. However, it is important to note that the commonly used 42% HFCS actually contains less fructose than sucrose, which is 50% fructose.)
Honey and molasses are two other carbohydrate syrup sweeteners that are sometimes deemed “healthier” due to the presence of trace minerals and vitamins. Honey is a natural high fructose syrup (38%), while molasses is predominantly sucrose. They are chosen for flavor, color enhancement, water management and binding properties. However, their applications are also limited by their characteristic flavor and color and the presence of enzymes.
        Next, Dominic Vellucci explored the bulk sweeteners which have about the same sweetness as sucrose, but fewer calories. Therefore, they can be used to substitute sugars in low-calorie foods while maintaining the same volume. The bulk sweeteners include tagatose and polyols which are commonly found in gums and mints. Tagatose is a naturally occurring sweetener that is non-cariogenic (does not cause cavities), has a 0.92x sweetness and provides 1.5 kcal per gram. Polyols, or sugar alcohols, which have reduced caloric values and a cooling affect ( endothermic heat of solution), includes sorbitol, mannitol, xylitol, erythritol, maltitol, isomalt, and lactitol. However, many of these bulk sweeteners have laxative effects and require a laxative threshold (g/day) warning.
       Currently, food industries are interested in artificial high intensity sweeteners which can be 10,000 times sweeter than sucrose. The primary high intensity sweeteners that are approved by the FDA are aspartame, neotame, Ace-K, sucralose (SPLENDA®), and saccharin. However, there are problems in substituting carbohydrate sweeteners with high intensity sweeteners due to the difference in taste, texture and viscosity, and the decrease in bulk since only a small amount of high intensity sweeteners is needed. The stability and solubility of the high intensity sweeteners are also issues to be considered by the food industry.  Aspartame, 180 times as sweet as sucrose, has a slight aftertaste and is used both as sole sweetener and as part of sweetener blends in dry mix products and some liquid beverages. However, Kraft has limited its used due to its instability in solution and shorter shelf-life; aspartame breaks down and loses some of its sweetness after five or six weeks of storage. Also, since aspartame can be metabolized, products like yogurt have to be overdosed with aspartame because the sweetness would decrease with time. However, aspartame is commonly used in products that are expected to be consumed within a few weeks of its production, such as carbonated drinks. Neotame is a modified and more stable version of aspartame. It is 8,000-10,000 times as sweet as sucrose, has zero calories, and is often used in sweetener blends and in some medications.
Ace-K is a stable high intensity sweetener that is used almost exclusively in blends. It is approximately 180 times as sweet as sucrose and has good synergy with aspartame. However, it does have a slight metallic aftertaste.
       Sucralose is an artificial high intensity sweetener derived from sucrose. It is 600 times as sweet as sucrose and has the best stability of all the high intensity sweeteners. It is tolerant to all types of processing and is an excellent candidate for thermal processes because it is very heat stable. However, it has little synergy with other sweeteners and has a sweet aftertaste. Currently, sucralose is the #1 selling table-top sweetener, partially due to its excellent advertising campaigns.
       Saccharin is widely used as an inexpensive alternative to sucrose. (The safety of saccharin has been re-affirmed in 2000.) Saccharin is approximately 300 times sweeter than sucrose, has a metallic aftertaste, and is stable under most processing conditions. It is found in food services and is primarily used for beverages and as a table-top sweetener.
       In response to consumers’ desire to lower caloric intake, the food industry has been researching innovative ways to incorporate reduced-calorie sugar substitutes into their products without changing their taste, texture or appearance. As a result of health and caloric concerns, these artificial sugar substitutes have already established a place for themselves in today’s society. Now, even natural high intensity sweeteners (Brazzein, a protein sweetener derived from the plant pentadiplandra brazzeana; Lo Han Kuo, a fruit harvested in China; Stevioside, a sweetener derived from the plant Stevia rebaudiana; and Thaumatin) have been developed in response to consumers’ health concerns and are now simply waiting for the FDA’s approval before jumping into the food market.

Stephen Gould, Environmental Protection Agency, <>, “Fun with Four Curves.”

        A look at some everyday applications of several classical curves of mathematics, including the cycloid and the catenary.  A Power Point presentation with animations  and at least a half-dozen demonstrations that teachers can perform in the classroom  will make these curves personal friends of yours!
       Joe Sencen started the meeting with a water powered electric clock. He connected leads to an ordinary wall clock in place of the 1.5 volt AA battery that powered it. One lead was connected to a coil of copper wire and the other lead to a chunk of magnesium retrieved from a discarded electric water heater. (There are pin sized holes in the glass lining of electric water heaters. Manufacturers have found it cheaper to install a magnesium sacrificial anode to slow down corrosion rather than to add a second glass coat to seal the pin holes.) When the magnesium and copper were dipped into a battery jar (bottom half of a cutoff plastic 2 liter soft drink bottle) filled with tap water, the clock worked. To keep the electrodes separated when unattended, Joe placed a cut off smaller soft drink bottle with holes punched in its side inside the larger battery jar. The holes allow the ions to flow.
       Dr. Stephen Gould introduced us to some interesting curves complete with their history, applications, and great demonstrations teachers can perform in the classroom. Curves can be found all around us. They are found in nature ? an eagle’s beak, morning glories, waterfalls ? and in architecture ? bridges, tunnels, houses, roofs, Eiffel Tower. Dr. Gould set off on this project to discover the applications of different curves after being inspired by the Famous Curve Index website which provides information on all the major curves.
       Dr. Gould began with a refresher on the more familiar curves: the conic sections. The first conic section is the circle, which is the section of a cone formed by the intersection of a right, circular cone with a horizontal plane. An ellipse is the intersection of the cone with a plane inclined less than the slope of the cone’s side. The ellipse can be drawn by attaching a looped string to two points (the foci) and tracing out the curve while keeping the string taut. To demonstrate the principle that the light or sound passes through one focus will pass through the other, Professor Gould cut an ellipse out of a foam board and lined the edge of the ellipse with reflectors. Then, he shined a beam of light through one focus which then reflected off the edge and shined through the other focus.
       The parabola is the intersection of the cone and a plane parallel to the cone’s side. Since it is the set of points equidistance from the focus and the directrix, the parabola can be folded out by first drawing a point (the focus) on a piece of paper and points along one edge of the paper acting as the directrix. Then the paper is folded once for each dot on the directrix so that the dot overlaps the focus. The resulting creases will form a parabola.
       Finally, the hyperbola is a conic section formed by the intersection of the cone with a plane inclined more to the base of the cone than to the side of the cone. The hyperboloid, or the three dimensional hyperbola, is the preferred shape for the cooling towers of nuclear plants. The reason behind it is that, structurally, it is the most cost efficient, providing the most strength for the least amount of concrete. A hyperboloid can be made in the classroom by joining two circular disks with equal lengths of string and then rotating one disk while keeping the strings taut.
       Next, Professor Gould introduced the tractrix curve. The origin of this curve is quite interesting. Suppose a dog is chewing a bone at a point along the y-axis. If he is held on a leash by his master who is standing at the origin, and the master suddenly walks along the x-axis, dragging the dog away from the bone while the dog makes a constant attempt to return to the bone, the path of the dog forms a tractrix. As a result, the tractrix, which means that which is dragged in Latin, is often called the Hundekurve or Schleppkurve in German (Hund = dog and schleppen = to drag). The tractrix is also known as the pseudosphere because it has a uniform negative curvature while the sphere has a uniform positive curvature.
       An application of the tractrix is in making Hi-fi loudspeakers that are designed to amplify sounds with minimum distortion. The problems to overcome are the impedance and the reflection of sound waves back into the horn, which distorts the sound. In the 1930s, an Englishman realized that a tractrix horn would lower the impedance to a minimum and the resulting constant wave front radii would reduce the amount of sound waves reflected back into the horn. As a result, a tractrix horn would have a higher power output and a better sound profile.
       A pending application of the tractrix is in the production of non-leaking valves used in appliances like burets. In burets, the valve wears faster at the wider end as it is frequently turned open and close. As a result, extended use of the valve will cause it to leak. The benefits of a tractrix valve is that all parts of the valve will wear at the same rate because the wear at the narrower end of the valve will be equal to the wear at the wider end due to the increased friction. Therefore, as the tractrix valve wears down, it will just shift down while still maintaining the tractrix shape and keeping the seal tight.
       The next curve was the catenary which is the curve of the lowest potential energy. A catenary can be easily demonstrated by holding the two ends of a flexible, inelastic, and uniform string (chain) so that it is hanging only under its own weight. An interesting relationship between the parabola and the catenary is that when a parabola is rolled along a straight line, its focus traces a catenary. Also, the curve joining two points that produces the structure with the minimum surface area when rotated 360 degrees is the catenary. The resulting catenoid can be illustrated with the help of soap film and two small hoops. By overlapping the two hoops dipped in soap film and slowly pulling them apart, a catenoid is formed.  The inverted catenary is also unique for it is the natural arch, or the strongest arch without any load on it. The inverted catenary is able to distribute the gravitational forces acting on it so that all the horizontal components cancel one another. Therefore, the structure is very stable because the net force is only acting vertically downwards.
       Then, Dr. Gould moved on to the cycloid and the involute of a circle, two curves that forms the basis for most gear teeth. The cycloid is the curve traced by a point on the circumference of a circle as it rolls along a straight line. The cycloid has an area three times that of the generating circle and a length eight times the radius of the circle. The curtate and the prolate cycloid are curves in the cycloid family and are formed when the generating point is inside and outside the circle respectively.
The involute of any curve can be visualized as having a thread wounded around the curve. Then, as the thread is held at a fixed point and unwounded while keeping the string taut, the path of the fixed point is the involute of the curve. For example, the involute of the catenary is the tractrix and the cycloid is the involute of itself.
The basic requirement for gears to work well together is that their tangential velocities are identical and constant. The cycloid family and the involute of a circle pass this basic requirement and are widely used in the gear industry. The gears with gear teeth the shape of cycloids has the least friction. However, they are harder to manufacture and less tolerant to slight shifts in gear position. On the other hand, the involute of a circle produces gears with more friction, but they are easier to manufacture and are more tolerant to shifts in gear position.
       Some other properties of the cycloid is that given two points A and B in a vertical plane, the inverted cycloid is the curve traced out by a point acted on only be gravity which starts at A and reaches B in the shortest time. Dr. Gould demonstrated with a large foam cycloid cutout that two balls rolled from any point along the cycloid will reach its center at the same time. Also, unlike pendulums swinging along a circular path, a pendulum swinging along a cycloidal path has a period independent of angular displacement and has been used in clocks

 “Demo Derby” An evening of non-stop demonstrations suitable for the science classroom by members of the Chemistry Teachers’ Club of New York and the Physics Teachers Club of New York.
Nonstop demonstrations ? in order of presentation ? by: Myra Hauben, Ivi Tamm, Al Delfiner, Sara Blumenstein, Amy Rosen, Zock Berit, John Augenstein, Tom Meyer, Jack DePalma, Steve Zellman, Joe Sencen, Bob Capacibo

The demonstration meeting, as usual, was the best attended of the year.

Dr. David Fairhurst, Colloid Consultants Ltd., 9 Westview Avenue, Congers, NY 10920 “Formulating Semi-solid Topical Delivery Systems: Development of a Microbicide for HIV.”

       Joe Sencen brought a large paper sheet with three (3) hand drawn “bull’s-eye” targets. He used magnets to quickly attach the sheet to the chalkboard and to show hits on the targets; some tight clusters, some widely spread, some centered and others off center. He then quizzed the group on the accuracy and precision of the hits. Joe said that this visualization makes it easier for his students to understand that percent error pertains to accuracy, not precision as some may think, and that “you can be precisely…wrong”.
       Dr. Bob Drake introduced the guest speaker, Dr. David Fairhurst, Colloid Consultants Ltd., 9 Westview Avenue, Congers, NY 10920, a graduate of the University of Liverpool. His topic was “Formulating Semi-solid Topical Delivery System for the Development of Microbicide for HIV,” and is funded by the Bill and Melinda Gates Foundation and IPM (International Partnership for Microbicides).
       Dr. Fairhurst began by alerting us to the rate at which the HIV/AIDS pandemic was increasing and placed emphasis on the vulnerability of females due to their social circumstances (position in relation to males in certain societies). Currently there are twice as many young women infected than men, and these women hold a greater chance of spreading the virus.
       Dr. Fairhurt’s is working on a gel that will prevent the infection of HIV altogether, and has emphasized that his success in formulating his product has come from his understanding of chemical reactions. He urged us to not be wary of formulation, but to embrace it. Dealing promptly with simple problems like aesthetics that might result in compliance sooner is much better than wasting time and funding later on.

Christopher Ward, Hommocks School, Mamaroneck, NY 10543, and Thomas Vesey, Gorton HS, Yonkers, NY 10703, “Using Video (Streaming and Nonstreaming) to enhance your Science Lesson.”

       Learn how to use video segments in inquiry based lessons (using NTTI Methodology): how to get on line using the 13/PBS/NYS purchased streaming site and download free video clips: other resources on the site and more. (We will also touch on how to use movie video clips to enhance a science lesson.)
The meeting started with two short demos by Joe Sencen, followed by the featured presenters, Chris Ward, Hommocks School, and Tom Vesey, Gorton HS,
       Chris and Tom demonstrated how to use videos interactively in the classroom. In addition to hands-on demonstrations, they distributed packets of resource information. They used resources from Channel Thirteen/WNET New York, the New York Times, and the Internet. Some of the contacts are: Thirteen/WNET at 212-560-6613,      Thirteen and WLIW21 will be hosting a K-12 Professional Development Conference on March 23-24, 2007, Pier 94, The UnConvention Center, 12th Avenue at 55th St, NYC.  PowerMediaPlus.Com at: or 800-324-5280.
There are literally thousands of movies and tens of thousands of video clips available on the Internet. Judicious use of a few short segments can enliven any lesson. But remember, the aim is for the clips to support the lesson, not overwhelm it.
       While these techniques can be used for grades K-12, Chris showed how he uses it very effectively with grade 8 earth science. Chris emphasized the need for the teacher to properly prepare and that the classroom have easy to use and easy to see display equipment. Used correctly, interactive video can enhance your lesson. Used incorrectly, it will waste everyone’s time. Warning: Much of the video on the Internet is under copy write. Careful how you use it if you plan to publish.
Joe Sencen’s first demo was designed to show how wave lengths other than the visible can bring out hidden features. He used a UV light and several varieties of soft drink cans. Codes are printed on the bottom of some of the cans which the UV light reveals. The Diet Pepsi, which was supposed to have a varnish on the bottom rim to make it slide more smoothly on the manufacturing conveyor belts, didn’t reveal anything
       Joe’s second demo showed a safe way of generating hydrogen gas. He calls the apparatus the Necnes gas generator (Sencen spelled backwards.). The key component is a specially prepared plastic pipette. The bulb, filled with mossy zinc, can be lowered and raised inside an Erlenmeyer flask that contains a small quantity of HCl acid. When the bulb, hanging from it’s stem, dips into the acid, it generates gas; gas generation stops when the bulb is raised above the acid. The materials for the Necnes generator should be available in every school lab.

List of Materials: Erlenmeyer flask, three hole rubber stopper to fit flask, short piece of glass tubing with right angle bend (gas delivery tube), plastic thistle tube with long stem, two plastic syringes, short length of straight of glass tubing, two short pieces of rubber tubing, plastic pipette, mossy zinc, HCl acid.
Prepare Pipette: Straighten one bend of a paperclip and heat the straightened end. Use the hot end to melt holes in the end of the pipette bulb to allow the acid to flow in and out when the bulb end is dipped. On the side of the bulb near the stem, melt a hole with a nail or screw. The hole should be large enough to insert mossy zinc chips.

Prepare Dipping Mechanism: Insert the short length of straight glass tubing into one hole of the stopper. Attach the short pieces of rubber tubing to each end of the glass tubing and attach a syringe to each piece of the rubber tubing. One syringe should be plunger in and the other plunger out. When one syringe is manipulated, the other is moved in the opposite direction. Melt a hole in the end of the plunger of the syringe that will be suspended inside the flask. Insert the stem of the pipette through the hole and make a knot in the stem so it will not slip through the hole. Assemble the dipping mechanism to the flask and adjust so that when the outside syringe is fully depressed, the end of the pipette bulb with the holes will be just above the bottom of the flask. Withdrawing the plunger raises the bulb.

Complete Assembly: Insert the right angle gas delivery tube and the thistle tube stem into the stopper. Adjust the thistle tube so that the end of the stem just clears the bottom of the flask. Put a few chips of zinc into the pipette bulb and seal the flask with the stopper assembly. Move the outside syringe plunger in and out. The inside plunger should move down and up. Leave in the up position. Add acid to the system until the level is approximately 1 to 2 cm above the thistle tube end.
To Use: Push the plunger in; the zinc dips into the acid and H2 gas is generated (see bubbles.) Withdraw plunger; the zinc rises above the acid level and the gas generation stops. Attach a rubber tube to the end of the right angle gas delivery tube and direct the gas to where it is needed. The thistle tube serves two purposes: a means for adding acid to the system and a pressure control/measuring system. Some pressure is needed to force the gas to where it is needed. This pressure will cause the acid to rise in the stem of the tube and fill the bulb. If the back pressure is great enough, the acid level in the flask will drop below the zinc and the gas generation will stop.

      Joe was urged to publish a description of the Necnes gas generator. He said he would submit it to Chem 13 News. This neat contraption was given away to Kristin Mayer, one very happy Chemistry teacher.
 

Dr. John L. Roeder, Calhoun School, New York, NY, nbsp;    “Energy Plans for the 21st Century.”

       Energy is both a basic physics concept and an important social issue. In an updated version of a talk Roeder presented to the American Association of Physics Teachers three years ago, he will describe activities by which students can learn energy principles in the classroom and discuss energy issues raised by energy plans from the National Energy Policy Development Group, the National Commission on Energy Policy, and the Natural Resources Defense Council.
       In leading up to a discussion of energy plans for the 21st century at our 17 November meeting, John Roeder, began by recounting his many involvements in energy education since he came to teach at The Calhoun School in 1973, the year of the Arab Oil Embargo. Most recently this has led him to develop a manual for the Physics Teaching Resource Agents of the American Association of Physics Teachers, Teaching About Energy.
       In this manual Roeder has activities for students to learn about energy as a basic science concept and to become more informed about energy issues that affect our future life on Earth, and his presentation involved both of these aspects of energy. To motivate the concepts of work and gravitational potential energy, he asks students to measure the force needed to pull a cart simulating a roller coaster up to the first hill for different slopes. When the cart goes down the hill, it loses gravitational potential energy and gains speed. Measuring the speed of the cart and plotting it versus gravitational potential energy loss, then using the “data linearization” approach of the Modeling Physics project, allows the conventional expression for kinetic energy to be derived.
       Other activities in the manual enable students to observe other energy transformations. Because of the Second Law of Thermodynamics, most energy transformations don’t occur with 100% efficiency, and Roeder marveled that the principle of energy conservation was discovered in spite of this.
        Energy conservation to the public, though, means something different from the First Law of Thermodynamics. It means not “using” more energy to do a job than we really need -- although, by the First Law of Thermodynamics, energy is not really “used” but really “converted” to a less useful form. Roeder concluded by reviewing the sources of energy “used” in the United States since the Arab Oil Embargo. He noted that the fossil fuel shortage which led to the Arab Oil Embargo turned out to be temporary then, though it did follow shortly the peak of American oil production. But, more than 30 years later, the world is approaching its peak in oil production, and after that increased demand and decreasing supply will produce a permanent shortage. Still, in spite of many warnings since the Arab Oil Embargo that the U.S. would need to wean itself from an energy diet of 85% fossil fuels, little progress has been made.
       Three energy plans for the 21st century have been developed during the current Bush Administration, one by the Administration itself, one in response to it by the “National Commission on Energy Policy” (NCEP), and a third by the Natural Resources Defense Council (NRDC). The Administration plan basically calls for continuing the energy status quo. The NCEP plan, developed in response to the Administration plan, pays a lot of attention to global warming from fossil fuel combustion and the development of cellulosic alcohol for transportation fuel, but sets no specific goals for renewable energy sources. On the other hand, the NRDC would phase out all fossil fuels in favor of renewables.

  Dr. Joe Schwarcz, Director, McGill Office for Science and Society, Department of Chemistry, MAASS Chemistry Building, McGill University, Montreal, Canada,

        “Have You Ever Wondered...” Why for years and years there were no red M&M's, or how to get that maraschino cherry to float in the syrup inside a Cherry Blossom? Why does popcorn pop? Why are there holes in Swiss cheese? Have you every considered why there are no nuts or grapes in Grape Nuts Flakes or why witches supposedly use broomsticks as a method of transportation? Why did Van Gogh mangle his ear? Were Agatha Christie's accounts of dastardly poisoning based on real science? Can chocolate really make you fall in love? etc.
        Al Delfiner used the overhead projector (a rapidly disappearing technology) to show a colorful comic (but accurate) evolution of the Periodic Table of the Elements. He found it on the Internet at The web page is maintained by the reDiscovery Institute, an organization devoted to spoofing creationisim and the Discovery Institute.
       Howard Spergel also used the overhead projector. He taped a polarizing filter to the upper lens and another to the ground glass. The filters were oriented at right angles to block the light. Rotating a third filter between the two brightened and dimmed the light. Placing various clear plastic parts between the filters revealed stress points in color. Stretching plastic tubing was particularly colorful.
       Joe Sencen demonstrated “action at a distance.” He brought in a flower container (the type they use in the supermarket) that had a large hole carved out from the bottom and the side of a plastic bag taped over top (doesn’t have to be drum tight.) He tapped on the bag and put out a candle flame a meter away. The opening should be at least 10 cm in diameter. A special trick you can do in class is to have two papar or plastic cups sit on top of one another, lip to lip, with a marble resting on the upper one. Attempt to knock the cup out but have the marble drop in.
       There are healthful reasons to eat fish. But there are also concerns about the level of PCBs (PolyChlorinated Biphenyls) they contain. And, as guest speaker Dr. Joe Schwarcz, went through similar considerations about a long list of products we eat or use in our daily lives in his presentation, he was left with the conclusion that in order to have a long life, one would have to be hungry, dirty, and smelly.
      But then came his rejoinder: none of the “scares” he had cited referred to any numbers. “Numbers are important,” he emphasized, noting that in the case of most contaminants of products we eat or use, the level of their presence is usually below the threshold of concern. Informing the public about the significance of these numbers is one of Schwarcz’s missions as Director of the Office for Science and Society at McGill University, Montreal, Canada   The McGill Office for Science and Society seeks to demystify science to the public, Schwarcz said. One of the ways he has been doing this is to answer questions about science from the public on radio station CJAD since 1980. His radio show is available to listen to on the Internet Sundays 3:00 PM Eastern Standard Time at . People are most interested in science that relates to their own life, he added, recalling one listener who was concerned about the presence of sodium triphosphate in a cleaning product and, once reconciled to the value of its use in cleaning products, was later disturbed to find it as an ingredient in bread.
       Scientific illiteracy is rampant, Schwarcz went on, and chemicals are equated with toxins. “Natural” is preferred, in spite of an abundance of “natural” organisms that are poisonous. On this issue Schwarcz singled out Kevin Trudeau, whose book, Natural Cures “They” Don’t Want You to Know About, seeks to convince the public that the corporate world has duped the public, while Trudeau himself is doing the same thing. Schwarcz pointed out that the Federal Trade Commission has banned Trudeau from selling “natural cure” scams, but that the first amendment to the U.S. Constitution precludes banning the books he writes.
Nor is Trudeau the only charlatan to be wary of. Schwarcz also cited Harvey and Marilyn Diamond and their book, Fit for Life. He also lamented that those pursuing cures proclaimed by charlatans were also avoiding efficaceous treatment.
       Some products promoted by charlatans can also be harmless and even humorous. One example was the Danish Water Revitalizer, a curved water pipe designed to restore “dead” water molecules whose bond angle had been reduced to 101o by L-shaped pipes. Another was an electrolysis device which claims to take toxins from feet soaked in it: the “removed toxins” are a rust-colored ferric hydroxide solution generated by the device.
      Communicating about science to the public is a big and important task, Schwarcz concluded, and most practicing scientists are not good at it. Climbing on a higher soapbox than the charlatans is important, he said, but more important is educating people. He said that students in his organic chemistry class know better than to ask whether natural vitamin C is better than synthetic. Schwarcz emphasized the importance of evaluating “authorities” in terms of the legitimacy of their academic background and whether they have a financial stake in what they advocate. He recommended New Scientist, newsletters published by Consumer’s Union, Harvard, and Berkeley, and Steven Barrett’s website
       Schwarcz also had a serious message about transfat to present, and he called on one of his interns, Melodie Ko, to present it. Introduced as a better alternative to saturated fats, which create higher levels of LDLs (low density lipids, known commonly as “bad cholesterol”), transfats are unsaturated, in that they have adjacent carbon atoms connected by double bonds, but with the hydrogen atoms bonded to this pair of carbon atoms on opposite sides (as opposed to the same side) of the carbon chain rather than on the same side. But it turns out that transfats also raise the level of LDLs  and also lower the levels of HDLs (high density lipids, known as “good cholesterol”). Thus transfats are “twice as bad” as saturated fats. All food labels must now list the amount of transfats, and most of the pastries we like (and should limit in our diet anyway) are rich in them. Unsaturated oils like olive and canola are the best for our health, but because they break down upon heating, they cannot be reused, and this presents a problem for restaurants.